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Standardised formatting.

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This commit is contained in:
simon 2017-08-14 20:18:13 +01:00
parent 31176e1f39
commit d7886550a6
25 changed files with 1131 additions and 949 deletions
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7
Makefile
View file

@ -8,6 +8,7 @@ DEPS := $(OBJS:.o=.d)
INC_DIRS := $(shell find $(SRC_DIRS) -type d)
INC_FLAGS := $(addprefix -I,$(INC_DIRS))
INDENT_FLAGS := -kr -nut -l79 -ts2
VERSION := "0.0.0"
@ -17,6 +18,12 @@ LDFLAGS := -lm
$(TARGET): $(OBJS)
$(CC) $(LDFLAGS) $(OBJS) -DVERSION=$(VERSION) -o $@ $(LDFLAGS) $(LOADLIBES) $(LDLIBS)
format:
indent $(INDENT_FLAGS) $(SRCS) src/*.h
test:
bash ./unit-tests.sh
.PHONY: clean
clean:
$(RM) $(TARGET) $(OBJS) $(DEPS)

116
src/conspage.c
View file

@ -19,8 +19,6 @@
#include "consspaceobject.h"
#include "conspage.h"
/**
* Flag indicating whether conspage initialisation has been done.
*/
@ -40,41 +38,50 @@ struct cons_pointer freelist = NIL;
/**
* An array of pointers to cons pages.
*/
struct cons_page* conspages[NCONSPAGES];
struct cons_page *conspages[NCONSPAGES];
/**
* Make a cons page whose serial number (i.e. index in the conspages directory) is pageno.
* Initialise all cells and prepend each to the freelist; if pageno is zero, do not prepend
* cells 0 and 1 to the freelist but initialise them as NIL and T respectively.
*/
void make_cons_page() {
struct cons_page* result = malloc( sizeof( struct cons_page));
void make_cons_page()
{
struct cons_page *result = malloc(sizeof(struct cons_page));
if ( result != NULL) {
if (result != NULL) {
conspages[initialised_cons_pages] = result;
for (int i = 0; i < CONSPAGESIZE; i++) {
struct cons_space_object * cell = &conspages[initialised_cons_pages]->cell[i];
if ( initialised_cons_pages == 0 && i < 2) {
if ( i == 0) {
/* initialise cell as NIL */
strncpy( &cell->tag.bytes[0], NILTAG, TAGLENGTH);
struct cons_space_object *cell =
&conspages[initialised_cons_pages]->cell[i];
if (initialised_cons_pages == 0 && i < 2) {
if (i == 0) {
/*
* initialise cell as NIL
*/
strncpy(&cell->tag.bytes[0], NILTAG, TAGLENGTH);
cell->count = MAXREFERENCE;
cell->payload.free.car = NIL;
cell->payload.free.cdr = NIL;
fprintf( stderr, "Allocated special cell NIL\n");
} else if ( i == 1) {
/* initialise cell as T */
strncpy( &cell->tag.bytes[0], TRUETAG, TAGLENGTH);
fprintf(stderr, "Allocated special cell NIL\n");
} else if (i == 1) {
/*
* initialise cell as T
*/
strncpy(&cell->tag.bytes[0], TRUETAG, TAGLENGTH);
cell->count = MAXREFERENCE;
cell->payload.free.car = (struct cons_pointer){ 0, 1};
cell->payload.free.cdr = (struct cons_pointer){ 0, 1};
fprintf( stderr, "Allocated special cell T\n");
cell->payload.free.car = (struct cons_pointer) {
0, 1};
cell->payload.free.cdr = (struct cons_pointer) {
0, 1};
fprintf(stderr, "Allocated special cell T\n");
}
} else {
/* otherwise, standard initialisation */
strncpy( &cell->tag.bytes[0], FREETAG, TAGLENGTH);
/*
* otherwise, standard initialisation
*/
strncpy(&cell->tag.bytes[0], FREETAG, TAGLENGTH);
cell->payload.free.car = NIL;
cell->payload.free.cdr = freelist;
freelist.page = initialised_cons_pages;
@ -82,57 +89,59 @@ void make_cons_page() {
}
}
initialised_cons_pages ++;
initialised_cons_pages++;
} else {
fprintf( stderr, "FATAL: Failed to allocate memory for cons page %d\n", initialised_cons_pages);
fprintf(stderr,
"FATAL: Failed to allocate memory for cons page %d\n",
initialised_cons_pages);
exit(1);
}
}
/**
* dump the allocated pages to this output stream.
*/
void dump_pages( FILE* output) {
for ( int i = 0; i < initialised_cons_pages; i++) {
fprintf( output, "\nDUMPING PAGE %d\n", i);
void dump_pages(FILE * output)
{
for (int i = 0; i < initialised_cons_pages; i++) {
fprintf(output, "\nDUMPING PAGE %d\n", i);
for ( int j = 0; j < CONSPAGESIZE; j++) {
dump_object( output, (struct cons_pointer){i, j});
for (int j = 0; j < CONSPAGESIZE; j++) {
dump_object(output, (struct cons_pointer) {
i, j});
}
}
}
/**
* Frees the cell at the specified pointer. Dangerous, primitive, low
* level.
*
* @pointer the cell to free
*/
void free_cell(struct cons_pointer pointer) {
struct cons_space_object* cell = &pointer2cell( pointer);
void free_cell(struct cons_pointer pointer)
{
struct cons_space_object *cell = &pointer2cell(pointer);
if ( !check_tag(pointer, FREETAG)) {
if ( cell->count == 0) {
strncpy( &cell->tag.bytes[0], FREETAG, 4);
if (!check_tag(pointer, FREETAG)) {
if (cell->count == 0) {
strncpy(&cell->tag.bytes[0], FREETAG, 4);
cell->payload.free.car = NIL;
cell->payload.free.cdr = freelist;
freelist = pointer;
} else {
fprintf( stderr,
fprintf(stderr,
"Attempt to free cell with %d dangling references at page %d, offset %d\n",
cell->count, pointer.page, pointer.offset);
}
} else {
fprintf( stderr,
fprintf(stderr,
"Attempt to free cell which is already FREE at page %d, offset %d\n",
pointer.page, pointer.offset);
}
}
/**
* Allocates a cell with the specified tag. Dangerous, primitive, low
* level.
@ -140,41 +149,43 @@ void free_cell(struct cons_pointer pointer) {
* @param tag the tag of the cell to allocate - must be a valid cons space tag.
* @return the cons pointer which refers to the cell allocated.
*/
struct cons_pointer allocate_cell( char* tag) {
struct cons_pointer allocate_cell(char *tag)
{
struct cons_pointer result = freelist;
if ( result.page == NIL.page && result.offset == NIL.offset) {
if (result.page == NIL.page && result.offset == NIL.offset) {
make_cons_page();
result = allocate_cell( tag);
result = allocate_cell(tag);
} else {
struct cons_space_object* cell = &pointer2cell(result);
struct cons_space_object *cell = &pointer2cell(result);
if ( strncmp( &cell->tag.bytes[0], FREETAG, TAGLENGTH) == 0) {
if (strncmp(&cell->tag.bytes[0], FREETAG, TAGLENGTH) == 0) {
freelist = cell->payload.free.cdr;
strncpy( &cell->tag.bytes[0], tag, 4);
strncpy(&cell->tag.bytes[0], tag, 4);
cell->count = 0;
cell->payload.cons.car = NIL;
cell->payload.cons.cdr = NIL;
fprintf( stderr, "Allocated cell of type '%s' at %d, %d \n",
tag, result.page, result.offset);
dump_object( stderr, result);
fprintf(stderr,
"Allocated cell of type '%s' at %d, %d \n", tag,
result.page, result.offset);
dump_object(stderr, result);
} else {
fprintf( stderr, "WARNING: Allocating non-free cell!");
fprintf(stderr, "WARNING: Allocating non-free cell!");
}
}
return result;
}
/**
* initialise the cons page system; to be called exactly once during startup.
*/
void initialise_cons_pages() {
if ( conspageinitihasbeencalled == false) {
void initialise_cons_pages()
{
if (conspageinitihasbeencalled == false) {
for (int i = 0; i < NCONSPAGES; i++) {
conspages[i] = (struct cons_page *) NULL;
}
@ -182,6 +193,7 @@ void initialise_cons_pages() {
make_cons_page();
conspageinitihasbeencalled = true;
} else {
fprintf( stderr, "WARNING: conspageinit() called a second or subsequent time\n");
fprintf(stderr,
"WARNING: conspageinit() called a second or subsequent time\n");
}
}

11
src/conspage.h
View file

@ -3,7 +3,6 @@
#ifndef __conspage_h
#define __conspage_h
/**
* the number of cons cells on a cons page. The maximum value this can be (and consequently,
* the size which, by version 1, it will default to) is the maximum value of an unsigned 32
@ -27,7 +26,6 @@ struct cons_page {
struct cons_space_object cell[CONSPAGESIZE];
};
/**
* The (global) pointer to the (global) freelist. Not sure whether this ultimately
* belongs in this file.
@ -37,8 +35,7 @@ extern struct cons_pointer freelist;
/**
* An array of pointers to cons pages.
*/
extern struct cons_page* conspages[NCONSPAGES];
extern struct cons_page *conspages[NCONSPAGES];
/**
* Frees the cell at the specified pointer. Dangerous, primitive, low
@ -48,7 +45,6 @@ extern struct cons_page* conspages[NCONSPAGES];
*/
void free_cell(struct cons_pointer pointer);
/**
* Allocates a cell with the specified tag. Dangerous, primitive, low
* level.
@ -56,8 +52,7 @@ void free_cell(struct cons_pointer pointer);
* @param tag the tag of the cell to allocate - must be a valid cons space tag.
* @return the cons pointer which refers to the cell allocated.
*/
struct cons_pointer allocate_cell( char* tag);
struct cons_pointer allocate_cell(char *tag);
/**
* initialise the cons page system; to be called exactly once during startup.
@ -67,6 +62,6 @@ void initialise_cons_pages();
/**
* dump the allocated pages to this output stream.
*/
void dump_pages( FILE* output);
void dump_pages(FILE * output);
#endif

148
src/consspaceobject.c
View file

@ -11,7 +11,9 @@
#include <stdint.h>
#include <stdlib.h>
#include <string.h>
/* wide characters */
/*
* wide characters
*/
#include <wchar.h>
#include <wctype.h>
@ -21,94 +23,94 @@
/**
* Check that the tag on the cell at this pointer is this tag
*/
int check_tag( struct cons_pointer pointer, char* tag) {
int check_tag(struct cons_pointer pointer, char *tag)
{
struct cons_space_object cell = pointer2cell(pointer);
return strncmp( &cell.tag.bytes[0], tag, TAGLENGTH) == 0;
return strncmp(&cell.tag.bytes[0], tag, TAGLENGTH) == 0;
}
/**
* increment the reference count of the object at this cons pointer.
*
* You can't roll over the reference count. Once it hits the maximum
* value you cannot increment further.
*/
void inc_ref( struct cons_pointer pointer) {
struct cons_space_object* cell = &pointer2cell( pointer);
void inc_ref(struct cons_pointer pointer)
{
struct cons_space_object *cell = &pointer2cell(pointer);
if (cell->count < MAXREFERENCE) {
cell->count ++;
cell->count++;
}
}
/**
* Decrement the reference count of the object at this cons pointer.
*
* If a count has reached MAXREFERENCE it cannot be decremented.
* If a count is decremented to zero the cell should be freed.
*/
void dec_ref( struct cons_pointer pointer) {
struct cons_space_object* cell = &pointer2cell( pointer);
void dec_ref(struct cons_pointer pointer)
{
struct cons_space_object *cell = &pointer2cell(pointer);
if (cell->count <= MAXREFERENCE) {
cell->count --;
cell->count--;
if (cell->count == 0) {
free_cell( pointer);
free_cell(pointer);
}
}
}
/**
* dump the object at this cons_pointer to this output stream.
*/
void dump_object( FILE* output, struct cons_pointer pointer) {
void dump_object(FILE * output, struct cons_pointer pointer)
{
struct cons_space_object cell = pointer2cell(pointer);
fwprintf( output,
fwprintf(output,
L"\tDumping %c%c%c%c (%d) at page %d, offset %d count %u\n",
cell.tag.bytes[0],
cell.tag.bytes[1],
cell.tag.bytes[2],
cell.tag.bytes[3],
cell.tag.value,
pointer.page,
pointer.offset,
cell.count);
cell.tag.value, pointer.page, pointer.offset, cell.count);
if ( check_tag(pointer, CONSTAG)) {
fwprintf( output,
if (check_tag(pointer, CONSTAG)) {
fwprintf(output,
L"\t\tCons cell: car at page %d offset %d, cdr at page %d offset %d\n",
cell.payload.cons.car.page, cell.payload.cons.car.offset,
cell.payload.cons.car.page,
cell.payload.cons.car.offset,
cell.payload.cons.cdr.page, cell.payload.cons.cdr.offset);
} else if ( check_tag(pointer, INTEGERTAG)) {
fwprintf( output,
L"\t\tInteger cell: value %ld\n",
cell.payload.integer.value);
} else if ( check_tag( pointer, FREETAG)) {
fwprintf( output, L"\t\tFree cell: next at page %d offset %d\n",
} else if (check_tag(pointer, INTEGERTAG)) {
fwprintf(output,
L"\t\tInteger cell: value %ld\n", cell.payload.integer.value);
} else if (check_tag(pointer, FREETAG)) {
fwprintf(output, L"\t\tFree cell: next at page %d offset %d\n",
cell.payload.cons.cdr.page, cell.payload.cons.cdr.offset);
} else if ( check_tag(pointer, REALTAG)) {
fwprintf( output, L"\t\tReal cell: value %Lf\n", cell.payload.real.value);
} else if ( check_tag( pointer, STRINGTAG)) {
fwprintf( output,
} else if (check_tag(pointer, REALTAG)) {
fwprintf(output, L"\t\tReal cell: value %Lf\n",
cell.payload.real.value);
} else if (check_tag(pointer, STRINGTAG)) {
fwprintf(output,
L"String cell: character '%1c' (%1d) next at page %2d offset %3d\n",
cell.payload.string.character, cell.payload.string.cdr.page,
cell.payload.string.cdr.offset);
cell.payload.string.character,
cell.payload.string.cdr.page, cell.payload.string.cdr.offset);
}
}
/**
* Construct a cons cell from this pair of pointers.
*/
struct cons_pointer make_cons( struct cons_pointer car, struct cons_pointer cdr) {
struct cons_pointer make_cons(struct cons_pointer car, struct cons_pointer cdr)
{
struct cons_pointer pointer = NIL;
pointer = allocate_cell( CONSTAG);
pointer = allocate_cell(CONSTAG);
struct cons_space_object* cell = &conspages[pointer.page]->cell[pointer.offset];
struct cons_space_object *cell =
&conspages[pointer.page]->cell[pointer.offset];
inc_ref(car);
inc_ref(cdr);
@ -121,11 +123,12 @@ struct cons_pointer make_cons( struct cons_pointer car, struct cons_pointer cdr)
/**
* Construct a cell which points to an executable Lisp special form.
*/
struct cons_pointer make_function( struct cons_pointer src,
struct cons_pointer (*executable)
(struct stack_frame*, struct cons_pointer)) {
struct cons_pointer pointer = allocate_cell( FUNCTIONTAG);
struct cons_space_object* cell = &pointer2cell(pointer);
struct cons_pointer
make_function(struct cons_pointer src, struct cons_pointer (*executable)
(struct stack_frame *, struct cons_pointer))
{
struct cons_pointer pointer = allocate_cell(FUNCTIONTAG);
struct cons_space_object *cell = &pointer2cell(pointer);
cell->payload.function.source = src;
cell->payload.function.executable = executable;
@ -139,21 +142,22 @@ struct cons_pointer make_function( struct cons_pointer src,
* has one character and a pointer to the next; in the last cell the
* pointer to next is NIL.
*/
struct cons_pointer make_string_like_thing( wint_t c,
struct cons_pointer tail,
char* tag) {
struct cons_pointer
make_string_like_thing(wint_t c, struct cons_pointer tail, char *tag)
{
struct cons_pointer pointer = NIL;
if ( check_tag( tail, tag) || check_tag( tail, NILTAG)) {
pointer = allocate_cell( tag);
struct cons_space_object* cell = &pointer2cell(pointer);
if (check_tag(tail, tag) || check_tag(tail, NILTAG)) {
pointer = allocate_cell(tag);
struct cons_space_object *cell = &pointer2cell(pointer);
inc_ref(tail);
cell->payload.string.character = c;
cell->payload.string.cdr.page = tail.page;
cell->payload.string.cdr.offset = tail.offset;
} else {
fwprintf( stderr, L"Warning: only NIL and %s can be appended to %s\n",
fwprintf(stderr,
L"Warning: only NIL and %s can be appended to %s\n",
tag, tag);
}
@ -166,27 +170,37 @@ struct cons_pointer make_string_like_thing( wint_t c,
* has one character and a pointer to the next; in the last cell the
* pointer to next is NIL.
*/
struct cons_pointer make_string( wint_t c, struct cons_pointer tail) {
return make_string_like_thing( c, tail, STRINGTAG);
struct cons_pointer make_string(wint_t c, struct cons_pointer tail)
{
return make_string_like_thing(c, tail, STRINGTAG);
}
/**
* Construct a symbol from this character and this tail.
*/
struct cons_pointer make_symbol( wint_t c, struct cons_pointer tail) {
return make_string_like_thing( c, tail, SYMBOLTAG);
struct cons_pointer make_symbol(wint_t c, struct cons_pointer tail)
{
return make_string_like_thing(c, tail, SYMBOLTAG);
}
/**
* Construct a cell which points to an executable Lisp special form.
*/
struct cons_pointer make_special( struct cons_pointer src,
struct cons_pointer (*executable)
struct cons_pointer
make_special(struct cons_pointer src, struct cons_pointer (*executable)
(struct cons_pointer s_expr,
struct cons_pointer env,
struct stack_frame* frame)) {
struct cons_pointer pointer = allocate_cell( SPECIALTAG);
struct cons_space_object* cell = &pointer2cell(pointer);
struct cons_pointer env, struct stack_frame * frame))
{
struct cons_pointer pointer = allocate_cell(SPECIALTAG);
struct cons_space_object *cell = &pointer2cell(pointer);
cell->payload.special.source = src;
cell->payload.special.executable = executable;
@ -197,11 +211,12 @@ struct cons_pointer make_special( struct cons_pointer src,
/**
* Return a lisp string representation of this old skool ASCII string.
*/
struct cons_pointer c_string_to_lisp_string( char* string) {
struct cons_pointer c_string_to_lisp_string(char *string)
{
struct cons_pointer result = NIL;
for ( int i = strlen( string); i > 0; i--) {
result = make_string( (wint_t)string[ i - 1], result);
for (int i = strlen(string); i > 0; i--) {
result = make_string((wint_t) string[i - 1], result);
}
return result;
@ -210,11 +225,12 @@ struct cons_pointer c_string_to_lisp_string( char* string) {
/**
* Return a lisp symbol representation of this old skool ASCII string.
*/
struct cons_pointer c_string_to_lisp_symbol( char* symbol) {
struct cons_pointer c_string_to_lisp_symbol(char *symbol)
{
struct cons_pointer result = NIL;
for ( int i = strlen( symbol); i > 0; i--) {
result = make_symbol( (wint_t)symbol[ i - 1], result);
for (int i = strlen(symbol); i > 0; i--) {
result = make_symbol((wint_t) symbol[i - 1], result);
}
return result;

141
src/consspaceobject.h
View file

@ -11,7 +11,9 @@
#include <stdbool.h>
#include <stdint.h>
#include <stdio.h>
/* wide characters */
/*
* wide characters
*/
#include <wchar.h>
#include <wctype.h>
@ -201,11 +203,14 @@
* An indirect pointer to a cons cell
*/
struct cons_pointer {
uint32_t page; /* the index of the page on which this cell resides */
uint32_t page; /* the index of the page on which this cell
* resides */
uint32_t offset; /* the index of the cell within the page */
};
/* number of arguments stored in a stack frame */
/*
* number of arguments stored in a stack frame
*/
#define args_in_frame 8
/**
@ -213,11 +218,12 @@ struct cons_pointer {
* here to avoid circularity. TODO: refactor.
*/
struct stack_frame {
struct stack_frame* previous; /* the previous frame */
struct stack_frame *previous; /* the previous frame */
struct cons_pointer arg[args_in_frame];
/* first 8 arument bindings */
struct cons_pointer more; /* list of any further argument
* bindings */
/*
* first 8 arument bindings
*/
struct cons_pointer more; /* list of any further argument bindings */
struct cons_pointer function; /* the function to be called */
};
@ -240,7 +246,8 @@ struct cons_payload {
*/
struct function_payload {
struct cons_pointer source;
struct cons_pointer (*executable)(struct stack_frame*, struct cons_pointer);
struct cons_pointer (*executable) (struct stack_frame *,
struct cons_pointer);
};
/**
@ -283,16 +290,16 @@ struct real_payload {
*/
struct special_payload {
struct cons_pointer source;
struct cons_pointer (*executable)(struct cons_pointer s_expr,
struct cons_pointer (*executable) (struct cons_pointer s_expr,
struct cons_pointer env,
struct stack_frame* frame);
struct stack_frame * frame);
};
/**
* payload of a read or write stream cell.
*/
struct stream_payload {
FILE * stream;
FILE *stream;
};
/**
@ -309,10 +316,12 @@ struct string_payload {
struct vectorp_payload {
union {
char bytes[TAGLENGTH]; /* the tag (type) of the vector-space
* object this cell points to, considered
* as bytes. NOTE that the vector space
* object should itself have the identical tag. */
char bytes[TAGLENGTH]; /* the tag (type) of the
* vector-space object this cell
* points to, considered as bytes.
* NOTE that the vector space object
* should itself have the identical
* tag. */
uint32_t value; /* the tag considered as a number */
} tag;
uint64_t address; /* the address of the actual vector space
@ -320,106 +329,144 @@ struct vectorp_payload {
* implement vector space) */
};
/**
* an object in cons space.
*/
struct cons_space_object {
union {
char bytes[TAGLENGTH]; /* the tag (type) of this cell, considered as bytes */
char bytes[TAGLENGTH]; /* the tag (type) of this cell,
* considered as bytes */
uint32_t value; /* the tag considered as a number */
} tag;
uint32_t count; /* the count of the number of references to this cell */
struct cons_pointer access; /* cons pointer to the access control list of this cell */
uint32_t count; /* the count of the number of references to
* this cell */
struct cons_pointer access; /* cons pointer to the access control list of
* this cell */
union {
/* if tag == CONSTAG */
/*
* if tag == CONSTAG
*/
struct cons_payload cons;
/* if tag == FREETAG */
/*
* if tag == FREETAG
*/
struct free_payload free;
/* if tag == FUNCTIONTAG */
/*
* if tag == FUNCTIONTAG
*/
struct function_payload function;
/* if tag == INTEGERTAG */
/*
* if tag == INTEGERTAG
*/
struct integer_payload integer;
/* if tag == NILTAG; we'll treat the special cell NIL as just a cons */
/*
* if tag == NILTAG; we'll treat the special cell NIL as just a cons
*/
struct cons_payload nil;
/* if tag == READTAG || tag == WRITETAG */
/*
* if tag == READTAG || tag == WRITETAG
*/
struct stream_payload stream;
/* if tag == REALTAG */
/*
* if tag == REALTAG
*/
struct real_payload real;
/* if tag == SPECIALTAG */
/*
* if tag == SPECIALTAG
*/
struct special_payload special;
/* if tag == STRINGTAG || tag == SYMBOLTAG */
/*
* if tag == STRINGTAG || tag == SYMBOLTAG
*/
struct string_payload string;
/* if tag == TRUETAG; we'll treat the special cell T as just a cons */
/*
* if tag == TRUETAG; we'll treat the special cell T as just a cons
*/
struct cons_payload t;
/* if tag == VECTORPTAG */
/*
* if tag == VECTORPTAG
*/
struct vectorp_payload vectorp;
} payload;
};
/**
* Check that the tag on the cell at this pointer is this tag
*/
int check_tag( struct cons_pointer pointer, char* tag);
int check_tag(struct cons_pointer pointer, char *tag);
/**
* increment the reference count of the object at this cons pointer
*/
void inc_ref( struct cons_pointer pointer);
void inc_ref(struct cons_pointer pointer);
/**
* decrement the reference count of the object at this cons pointer
*/
void dec_ref( struct cons_pointer pointer);
void dec_ref(struct cons_pointer pointer);
/**
* dump the object at this cons_pointer to this output stream.
*/
void dump_object( FILE* output, struct cons_pointer pointer);
void dump_object(FILE * output, struct cons_pointer pointer);
struct cons_pointer make_cons( struct cons_pointer car, struct cons_pointer cdr);
struct cons_pointer make_cons(struct cons_pointer car,
struct cons_pointer cdr);
/**
* Construct a cell which points to an executable Lisp special form.
*/
struct cons_pointer make_function( struct cons_pointer src,
struct cons_pointer make_function(struct cons_pointer src,
struct cons_pointer (*executable)
(struct stack_frame*, struct cons_pointer));
(struct stack_frame *,
struct cons_pointer));
/**
* Construct a cell which points to an executable Lisp special form.
*/
struct cons_pointer make_special( struct cons_pointer src,
struct cons_pointer make_special(struct cons_pointer src,
struct cons_pointer (*executable)
(struct cons_pointer s_expr,
struct cons_pointer env,
struct stack_frame* frame));
struct stack_frame * frame));
/**
* Construct a string from this character and this tail. A string is
* implemented as a flat list of cells each of which has one character and a
* pointer to the next; in the last cell the pointer to next is NIL.
*/
struct cons_pointer make_string( wint_t c, struct cons_pointer tail);
struct cons_pointer make_string(wint_t c, struct cons_pointer tail);
/**
* Construct a symbol from this character and this tail. A symbol is identical
* to a string except for having a different tag.
*/
struct cons_pointer make_symbol( wint_t c, struct cons_pointer tail);
struct cons_pointer make_symbol(wint_t c, struct cons_pointer tail);
/**
* Return a lisp string representation of this old skool ASCII string.
*/
struct cons_pointer c_string_to_lisp_string( char* string);
struct cons_pointer c_string_to_lisp_string(char *string);
/**
* Return a lisp symbol representation of this old skool ASCII string.
*/
struct cons_pointer c_string_to_lisp_symbol( char* symbol);
struct cons_pointer c_string_to_lisp_symbol(char *symbol);
#endif

64
src/equal.c
View file

@ -18,44 +18,54 @@
* Shallow, and thus cheap, equality: true if these two objects are
* the same object, else false.
*/
bool eq( struct cons_pointer a, struct cons_pointer b) {
bool eq(struct cons_pointer a, struct cons_pointer b)
{
return ((a.page == b.page) && (a.offset == b.offset));
}
/**
* Deep, and thus expensive, equality: true if these two objects have
* identical structure, else false.
*/
bool equal( struct cons_pointer a, struct cons_pointer b) {
bool result = eq( a, b);
bool equal(struct cons_pointer a, struct cons_pointer b)
{
bool result = eq(a, b);
if ( ! result) {
struct cons_space_object* cell_a = &pointer2cell( a);
struct cons_space_object* cell_b = &pointer2cell( b);
if (!result) {
struct cons_space_object *cell_a = &pointer2cell(a);
struct cons_space_object *cell_b = &pointer2cell(b);
if ( consp( a) && consp( b)) {
result = equal( cell_a->payload.cons.car, cell_b->payload.cons.car) &&
equal( cell_a->payload.cons.cdr, cell_b->payload.cons.cdr);
} else if ( stringp( a) && stringp( b)) {
/* slightly complex because a string may or may not have a '\0' cell
* at the end, but I'll ignore that for now. I think in practice only
* the empty string will. */
result = cell_a->payload.string.character == cell_b->payload.string.character &&
equal( cell_a->payload.string.cdr, cell_b->payload.string.cdr);
} else if ( numberp( a) && numberp( b)) {
double num_a = numeric_value( a);
double num_b = numeric_value( b);
double max = fabs( num_a) > fabs( num_b) ? fabs( num_a) : fabs( num_b);
if (consp(a) && consp(b)) {
result = equal(cell_a->payload.cons.car, cell_b->payload.cons.car)
&& equal(cell_a->payload.cons.cdr, cell_b->payload.cons.cdr);
} else if (stringp(a) && stringp(b)) {
/*
* slightly complex because a string may or may not have a '\0'
* cell at the end, but I'll ignore that for now. I think in
* practice only the empty string will.
*/
result =
cell_a->payload.string.character ==
cell_b->payload.string.character
&& equal(cell_a->payload.string.cdr,
cell_b->payload.string.cdr);
} else if (numberp(a) && numberp(b)) {
double num_a = numeric_value(a);
double num_b = numeric_value(b);
double max = fabs(num_a) > fabs(num_b) ? fabs(num_a) : fabs(num_b);
/* not more different than one part in a million - close enough */
result = fabs( num_a - num_b) < (max / 1000000.0);
/*
* not more different than one part in a million - close enough
*/
result = fabs(num_a - num_b) < (max / 1000000.0);
}
/* there's only supposed ever to be one T and one NIL cell, so each should
* be caught by eq; equality of vector-space objects is a whole other ball
* game so we won't deal with it now (and indeedmay never). I'm not certain
* what equality means for read and write streams, so I'll ignore them, too,
* for now.*/
/*
* there's only supposed ever to be one T and one NIL cell, so each
* should be caught by eq; equality of vector-space objects is a whole
* other ball game so we won't deal with it now (and indeedmay never).
* I'm not certain what equality means for read and write streams, so
* I'll ignore them, too, for now.
*/
}
return result;

4
src/equal.h
View file

@ -19,12 +19,12 @@
* Shallow, and thus cheap, equality: true if these two objects are
* the same object, else false.
*/
bool eq( struct cons_pointer a, struct cons_pointer b);
bool eq(struct cons_pointer a, struct cons_pointer b);
/**
* Deep, and thus expensive, equality: true if these two objects have
* identical structure, else false.
*/
bool equal( struct cons_pointer a, struct cons_pointer b);
bool equal(struct cons_pointer a, struct cons_pointer b);
#endif

86
src/init.c
View file

@ -21,21 +21,34 @@
#include "lispops.h"
#include "repl.h"
void bind_function( char* name, struct cons_pointer (*executable)
(struct stack_frame*, struct cons_pointer)) {
deep_bind( intern( c_string_to_lisp_symbol( name), oblist ),
make_function( NIL, executable));
void bind_function(char *name, struct cons_pointer (*executable)
(struct stack_frame *, struct cons_pointer))
{
deep_bind(intern(c_string_to_lisp_symbol(name), oblist),
make_function(NIL, executable));
}
void bind_special( char* name, struct cons_pointer (*executable)
void bind_special(char *name, struct cons_pointer (*executable)
(struct cons_pointer s_expr, struct cons_pointer env,
struct stack_frame* frame)) {
deep_bind( intern( c_string_to_lisp_symbol( name), oblist ),
make_special( NIL, executable));
struct stack_frame * frame))
{
deep_bind(intern(c_string_to_lisp_symbol(name), oblist),
make_special(NIL, executable));
}
int main (int argc, char *argv[]) {
/* attempt to set wide character acceptance on all streams */
int main(int argc, char *argv[])
{
/*
* attempt to set wide character acceptance on all streams
*/
fwide(stdin, 1);
fwide(stdout, 1);
fwide(stderr, 1);
@ -43,10 +56,8 @@ int main (int argc, char *argv[]) {
bool dump_at_end = false;
bool show_prompt = false;
while ((option = getopt (argc, argv, "pd")) != -1)
{
switch (option)
{
while ((option = getopt(argc, argv, "pd")) != -1) {
switch (option) {
case 'd':
dump_at_end = true;
break;
@ -54,42 +65,49 @@ int main (int argc, char *argv[]) {
show_prompt = true;
break;
default:
fprintf( stderr, "Unexpected option %c\n", option);
fprintf(stderr, "Unexpected option %c\n", option);
break;
}
}
if (show_prompt) {
fprintf( stdout, "Post scarcity software environment version %s\n\n", VERSION);
fprintf(stdout,
"Post scarcity software environment version %s\n\n", VERSION);
}
initialise_cons_pages();
/* privileged variables (keywords) */
deep_bind( intern( c_string_to_lisp_string( "nil"), oblist), NIL);
deep_bind( intern( c_string_to_lisp_string( "t"), oblist), TRUE);
/*
* privileged variables (keywords)
*/
deep_bind(intern(c_string_to_lisp_string("nil"), oblist), NIL);
deep_bind(intern(c_string_to_lisp_string("t"), oblist), TRUE);
/* primitive function operations */
bind_function( "assoc", &lisp_assoc);
bind_function( "car", &lisp_car);
bind_function( "cdr", &lisp_cdr);
bind_function( "cons", &lisp_cons);
bind_function( "eq", &lisp_eq);
bind_function( "equal", &lisp_equal);
bind_function( "read", &lisp_read);
bind_function( "print", &lisp_print);
/*
* primitive function operations
*/
bind_function("assoc", &lisp_assoc);
bind_function("car", &lisp_car);
bind_function("cdr", &lisp_cdr);
bind_function("cons", &lisp_cons);
bind_function("eq", &lisp_eq);
bind_function("equal", &lisp_equal);
bind_function("read", &lisp_read);
bind_function("print", &lisp_print);
/* primitive special forms */
bind_special( "apply", &lisp_apply);
bind_special( "eval", &lisp_eval);
bind_special( "quote", &lisp_quote);
/*
* primitive special forms
*/
bind_special("apply", &lisp_apply);
bind_special("eval", &lisp_eval);
bind_special("quote", &lisp_quote);
repl(stdin, stdout, stderr, show_prompt);
// print( stdout, lisp_eval( input, oblist, NULL));
if ( dump_at_end) {
if (dump_at_end) {
dump_pages(stderr);
}
return(0);
return (0);
}

18
src/integer.c
View file

@ -19,28 +19,28 @@
* as a cons-space object. Cell may in principle be any kind of number,
* but only integers and reals are so far implemented.
*/
double numeric_value( struct cons_pointer pointer) {
double numeric_value(struct cons_pointer pointer)
{
double result = NAN;
struct cons_space_object* cell = &pointer2cell(pointer);
struct cons_space_object *cell = &pointer2cell(pointer);
if ( integerp( pointer)) {
if (integerp(pointer)) {
result = (double) cell->payload.integer.value;
} else if ( realp( pointer)) {
} else if (realp(pointer)) {
result = cell->payload.real.value;
}
return result;
}
/**
* Allocate an integer cell representing this value and return a cons pointer to it.
*/
struct cons_pointer make_integer( int value) {
struct cons_pointer result = allocate_cell( INTEGERTAG);
struct cons_space_object* cell = &pointer2cell(result);
struct cons_pointer make_integer(int value)
{
struct cons_pointer result = allocate_cell(INTEGERTAG);
struct cons_space_object *cell = &pointer2cell(result);
cell->payload.integer.value = value;
return result;
}

4
src/integer.h
View file

@ -11,11 +11,11 @@
#ifndef __integer_h
#define __integer_h
double numeric_value( struct cons_pointer pointer);
double numeric_value(struct cons_pointer pointer);
/**
* Allocate an integer cell representing this value and return a cons pointer to it.
*/
struct cons_pointer make_integer( int value);
struct cons_pointer make_integer(int value);
#endif

58
src/intern.c
View file

@ -43,16 +43,18 @@ struct cons_pointer oblist = NIL;
* from the store (so that later when we want to retrieve a value, an eq test
* will work); otherwise return NIL.
*/
struct cons_pointer internedp( struct cons_pointer key, struct cons_pointer store) {
struct cons_pointer
internedp(struct cons_pointer key, struct cons_pointer store)
{
struct cons_pointer result = NIL;
for ( struct cons_pointer next = store;
nilp( result) && consp( next);
next = pointer2cell( next).payload.cons.cdr) {
for (struct cons_pointer next = store;
nilp(result) && consp(next);
next = pointer2cell(next).payload.cons.cdr) {
struct cons_space_object entry =
pointer2cell( pointer2cell( next).payload.cons.car);
pointer2cell(pointer2cell(next).payload.cons.car);
if ( equal( key, entry.payload.cons.car)) {
if (equal(key, entry.payload.cons.car)) {
result = entry.payload.cons.car;
}
}
@ -68,16 +70,16 @@ struct cons_pointer internedp( struct cons_pointer key, struct cons_pointer stor
* If this key is lexically identical to a key in this store, return the value
* of that key from the store; otherwise return NIL.
*/
struct cons_pointer c_assoc( struct cons_pointer key, struct cons_pointer store) {
struct cons_pointer c_assoc(struct cons_pointer key, struct cons_pointer store)
{
struct cons_pointer result = NIL;
for ( struct cons_pointer next = store;
consp( next);
next = pointer2cell( next).payload.cons.cdr) {
for (struct cons_pointer next = store;
consp(next); next = pointer2cell(next).payload.cons.cdr) {
struct cons_space_object entry =
pointer2cell( pointer2cell( next).payload.cons.car);
pointer2cell(pointer2cell(next).payload.cons.car);
if ( equal( key, entry.payload.cons.car)) {
if (equal(key, entry.payload.cons.car)) {
result = entry.payload.cons.cdr;
break;
}
@ -86,41 +88,45 @@ struct cons_pointer c_assoc( struct cons_pointer key, struct cons_pointer store)
return result;
}
/**
* Return a new key/value store containing all the key/value pairs in this store
* with this key/value pair added to the front.
*/
struct cons_pointer bind( struct cons_pointer key, struct cons_pointer value,
struct cons_pointer store) {
return make_cons( make_cons( key, value), store);
struct cons_pointer
bind(struct cons_pointer key, struct cons_pointer value,
struct cons_pointer store)
{
return make_cons(make_cons(key, value), store);
}
/**
* Binds this key to this value in the global oblist, but doesn't affect the
* current environment. May not be useful except in bootstrapping (and even
* there it may not be especially useful).
*/
struct cons_pointer deep_bind( struct cons_pointer key, struct cons_pointer value) {
oblist = bind( key, value, oblist);
struct cons_pointer
deep_bind(struct cons_pointer key, struct cons_pointer value)
{
oblist = bind(key, value, oblist);
return oblist;
}
/**
* Ensure that a canonical copy of this key is bound in this environment, and
* return that canonical copy. If there is currently no such binding, create one
* with the value NIL.
*/
struct cons_pointer intern( struct cons_pointer key,
struct cons_pointer environment) {
struct cons_pointer
intern(struct cons_pointer key, struct cons_pointer environment)
{
struct cons_pointer result = environment;
struct cons_pointer canonical = internedp( key, environment);
struct cons_pointer canonical = internedp(key, environment);
if ( nilp( canonical)) {
/* not currently bound */
result = bind( key, NIL, environment);
if (nilp(canonical)) {
/*
* not currently bound
*/
result = bind(key, NIL, environment);
}
return result;

15
src/intern.h
View file

@ -17,7 +17,6 @@
* Licensed under GPL version 2.0, or, at your option, any later version.
*/
#ifndef __intern_h
#define __intern_h
@ -28,35 +27,37 @@ extern struct cons_pointer oblist;
* implementation a store is just an assoc list, but in future it might be a
* namespace, a regularity or a homogeneity.
*/
struct cons_pointer c_assoc( struct cons_pointer key, struct cons_pointer store);
struct cons_pointer c_assoc(struct cons_pointer key,
struct cons_pointer store);
/**
* Return true if this key is present as a key in this enviroment, defaulting to
* the oblist if no environment is passed.
*/
struct cons_pointer internedp( struct cons_pointer key,
struct cons_pointer internedp(struct cons_pointer key,
struct cons_pointer environment);
/**
* Return a new key/value store containing all the key/value pairs in this store
* with this key/value pair added to the front.
*/
struct cons_pointer bind( struct cons_pointer key, struct cons_pointer value,
struct cons_pointer store);
struct cons_pointer bind(struct cons_pointer key,
struct cons_pointer value, struct cons_pointer store);
/**
* Binds this key to this value in the global oblist, but doesn't affect the
* current environment. May not be useful except in bootstrapping (and even
* there it may not be especially useful).
*/
struct cons_pointer deep_bind( struct cons_pointer key, struct cons_pointer value);
struct cons_pointer deep_bind(struct cons_pointer key,
struct cons_pointer value);
/**
* Ensure that a canonical copy of this key is bound in this environment, and
* return that canonical copy. If there is currently no such binding, create one
* with the value NIL.
*/
struct cons_pointer intern( struct cons_pointer key,
struct cons_pointer intern(struct cons_pointer key,
struct cons_pointer environment);
#endif

243
src/lispops.c
View file

@ -49,11 +49,12 @@
/**
* Implementation of car in C. If arg is not a cons, does not error but returns nil.
*/
struct cons_pointer c_car( struct cons_pointer arg) {
struct cons_pointer c_car(struct cons_pointer arg)
{
struct cons_pointer result = NIL;
if ( consp(arg)) {
result = pointer2cell( arg).payload.cons.car;
if (consp(arg)) {
result = pointer2cell(arg).payload.cons.car;
}
return result;
@ -62,11 +63,12 @@ struct cons_pointer c_car( struct cons_pointer arg) {
/**
* Implementation of cdr in C. If arg is not a cons, does not error but returns nil.
*/
struct cons_pointer c_cdr( struct cons_pointer arg) {
struct cons_pointer c_cdr(struct cons_pointer arg)
{
struct cons_pointer result = NIL;
if ( consp(arg)) {
result = pointer2cell( arg).payload.cons.cdr;
if (consp(arg)) {
result = pointer2cell(arg).payload.cons.cdr;
}
return result;
@ -78,57 +80,66 @@ struct cons_pointer c_cdr( struct cons_pointer arg) {
* I'm now confused about whether at this stage I actually need an apply special form,
* and if so how it differs from eval.
*/
struct cons_pointer lisp_apply( struct cons_pointer args, struct cons_pointer env,
struct stack_frame* frame) {
struct cons_pointer
lisp_apply(struct cons_pointer args, struct cons_pointer env,
struct stack_frame *frame)
{
struct cons_pointer result = args;
if ( consp( args)) {
lisp_eval( args, env, frame);
if (consp(args)) {
lisp_eval(args, env, frame);
}
return result;
}
struct cons_pointer eval_cons( struct cons_pointer s_expr, struct cons_pointer env,
struct stack_frame* my_frame) {
struct cons_pointer
eval_cons(struct cons_pointer s_expr, struct cons_pointer env,
struct stack_frame *my_frame)
{
struct cons_pointer result = NIL;
struct cons_pointer fn_pointer = lisp_eval( c_car( s_expr), env, my_frame);
struct cons_space_object fn_cell = pointer2cell( fn_pointer);
struct cons_pointer args = c_cdr( s_expr);
struct cons_pointer fn_pointer = lisp_eval(c_car(s_expr), env, my_frame);
struct cons_space_object fn_cell = pointer2cell(fn_pointer);
struct cons_pointer args = c_cdr(s_expr);
switch ( fn_cell.tag.value) {
case SPECIALTV :
switch (fn_cell.tag.value) {
case SPECIALTV:
{
struct cons_space_object special = pointer2cell( fn_pointer);
result = (*special.payload.special.executable)( args, env, my_frame);
struct cons_space_object special = pointer2cell(fn_pointer);
result =
(*special.payload.special.executable) (args, env, my_frame);
}
break;
case FUNCTIONTV :
/* actually, this is apply */
case FUNCTIONTV:
/*
* actually, this is apply
*/
{
struct cons_space_object function = pointer2cell( fn_pointer);
struct stack_frame* frame = make_stack_frame( my_frame, args, env);
struct cons_space_object function = pointer2cell(fn_pointer);
struct stack_frame *frame = make_stack_frame(my_frame, args, env);
/* the trick: pass the remaining arguments and environment to
the executable code which is the payload of the function
object. */
result = (*function.payload.function.executable)( frame, env);
free_stack_frame( frame);
/*
* the trick: pass the remaining arguments and environment to the
* executable code which is the payload of the function object.
*/
result = (*function.payload.function.executable) (frame, env);
free_stack_frame(frame);
}
break;
default :
default:
{
char* buffer = malloc( 1024);
memset( buffer, '\0', 1024);
sprintf( buffer,
char *buffer = malloc(1024);
memset(buffer, '\0', 1024);
sprintf(buffer,
"Unexpected cell with tag %d (%c%c%c%c) in function position",
fn_cell.tag.value, fn_cell.tag.bytes[0], fn_cell.tag.bytes[1],
fn_cell.tag.bytes[2], fn_cell.tag.bytes[3]);
struct cons_pointer message = c_string_to_lisp_string( buffer);
free( buffer);
result = lisp_throw( message, my_frame);
fn_cell.tag.value, fn_cell.tag.bytes[0],
fn_cell.tag.bytes[1], fn_cell.tag.bytes[2],
fn_cell.tag.bytes[3]);
struct cons_pointer message = c_string_to_lisp_string(buffer);
free(buffer);
result = lisp_throw(message, my_frame);
}
}
@ -148,38 +159,43 @@ struct cons_pointer eval_cons( struct cons_pointer s_expr, struct cons_pointer e
* passes them in a stack frame as arguments to the function.
* If a special form, passes the cdr of s_expr to the special form as argument.
*/
struct cons_pointer lisp_eval( struct cons_pointer s_expr, struct cons_pointer env,
struct stack_frame* previous) {
struct cons_pointer
lisp_eval(struct cons_pointer s_expr, struct cons_pointer env,
struct stack_frame *previous)
{
struct cons_pointer result = s_expr;
struct cons_space_object cell = pointer2cell( s_expr);
struct stack_frame* my_frame =
make_stack_frame( previous, make_cons( s_expr, NIL), env);
struct cons_space_object cell = pointer2cell(s_expr);
struct stack_frame *my_frame =
make_stack_frame(previous, make_cons(s_expr, NIL), env);
switch ( cell.tag.value) {
case CONSTV :
result = eval_cons( s_expr, env, my_frame);
switch (cell.tag.value) {
case CONSTV:
result = eval_cons(s_expr, env, my_frame);
break;
case SYMBOLTV :
case SYMBOLTV:
{
struct cons_pointer canonical = internedp( s_expr, env);
if ( nilp( canonical)) {
struct cons_pointer canonical = internedp(s_expr, env);
if (nilp(canonical)) {
struct cons_pointer message =
c_string_to_lisp_string( "Attempt to take value of unbound symbol.");
result = lisp_throw( message, my_frame);
c_string_to_lisp_string
("Attempt to take value of unbound symbol.");
result = lisp_throw(message, my_frame);
} else {
result = c_assoc( canonical, env);
result = c_assoc(canonical, env);
}
}
break;
/* the Clojure practice of having a map serve in the function
* place of an s-expression is a good one and I should adopt it;
* also if the object is a consp it could be interpretable
* source code but in the long run I don't want an interpreter,
* and if I can get away without so much the better. */
/*
* the Clojure practice of having a map serve in the function place of
* an s-expression is a good one and I should adopt it; also if the
* object is a consp it could be interpretable source code but in the
* long run I don't want an interpreter, and if I can get away without
* so much the better.
*/
}
free_stack_frame( my_frame);
free_stack_frame(my_frame);
return result;
}
@ -191,9 +207,11 @@ struct cons_pointer lisp_eval( struct cons_pointer s_expr, struct cons_pointer e
* Returns its argument (strictly first argument - only one is expected but
* this isn't at this stage checked) unevaluated.
*/
struct cons_pointer lisp_quote( struct cons_pointer args, struct cons_pointer env,
struct stack_frame* frame) {
return c_car( args);
struct cons_pointer
lisp_quote(struct cons_pointer args, struct cons_pointer env,
struct stack_frame *frame)
{
return c_car(args);
}
/**
@ -204,18 +222,20 @@ struct cons_pointer lisp_quote( struct cons_pointer args, struct cons_pointer en
* cdr is nill, and b is of type string, then returns a new string cell;
* otherwise returns a new cons cell.
*/
struct cons_pointer lisp_cons(struct stack_frame* frame, struct cons_pointer env) {
struct cons_pointer
lisp_cons(struct stack_frame *frame, struct cons_pointer env)
{
struct cons_pointer car = frame->arg[0];
struct cons_pointer cdr = frame->arg[1];
struct cons_pointer result;
if ( nilp( car) && nilp( cdr)) {
if (nilp(car) && nilp(cdr)) {
return NIL;
} else if ( stringp( car) && stringp( cdr) &&
nilp( pointer2cell( car).payload.string.cdr)) {
result = make_string( pointer2cell( car).payload.string.character, cdr);
} else if (stringp(car) && stringp(cdr) &&
nilp(pointer2cell(car).payload.string.cdr)) {
result = make_string(pointer2cell(car).payload.string.character, cdr);
} else {
result = make_cons( car, cdr);
result = make_cons(car, cdr);
}
return result;
@ -226,43 +246,46 @@ struct cons_pointer lisp_cons(struct stack_frame* frame, struct cons_pointer env
* Returns the first item (head) of a sequence. Valid for cons cells,
* strings, and TODO read streams and other things which can be considered as sequences.
*/
struct cons_pointer lisp_car(struct stack_frame* frame, struct cons_pointer env) {
struct cons_pointer
lisp_car(struct stack_frame *frame, struct cons_pointer env)
{
struct cons_pointer result = NIL;
if ( consp( frame->arg[ 0])) {
struct cons_space_object cell = pointer2cell( frame->arg[ 0]);
if (consp(frame->arg[0])) {
struct cons_space_object cell = pointer2cell(frame->arg[0]);
result = cell.payload.cons.car;
} else if ( stringp( frame->arg[ 0])) {
struct cons_space_object cell = pointer2cell( frame->arg[ 0]);
result = make_string( cell.payload.string.character, NIL);
} else if (stringp(frame->arg[0])) {
struct cons_space_object cell = pointer2cell(frame->arg[0]);
result = make_string(cell.payload.string.character, NIL);
} else {
struct cons_pointer message =
c_string_to_lisp_string( "Attempt to take CAR/CDR of non sequence");
result = lisp_throw( message, frame);
c_string_to_lisp_string("Attempt to take CAR/CDR of non sequence");
result = lisp_throw(message, frame);
}
return result;
}
/**
* (cdr s_expr)
* Returns the remainder of a sequence when the head is removed. Valid for cons cells,
* strings, and TODO read streams and other things which can be considered as sequences.
*/
struct cons_pointer lisp_cdr(struct stack_frame* frame, struct cons_pointer env) {
struct cons_pointer
lisp_cdr(struct stack_frame *frame, struct cons_pointer env)
{
struct cons_pointer result = NIL;
if ( consp( frame->arg[ 0])) {
struct cons_space_object cell = pointer2cell( frame->arg[ 0]);
if (consp(frame->arg[0])) {
struct cons_space_object cell = pointer2cell(frame->arg[0]);
result = cell.payload.cons.car;
} else if ( stringp( frame->arg[ 0])) {
struct cons_space_object cell = pointer2cell( frame->arg[ 0]);
} else if (stringp(frame->arg[0])) {
struct cons_space_object cell = pointer2cell(frame->arg[0]);
result = cell.payload.string.cdr;
} else {
struct cons_pointer message =
c_string_to_lisp_string( "Attempt to take CAR/CDR of non sequence");
result = lisp_throw( message, frame);
c_string_to_lisp_string("Attempt to take CAR/CDR of non sequence");
result = lisp_throw(message, frame);
}
return result;
@ -272,24 +295,29 @@ struct cons_pointer lisp_cdr(struct stack_frame* frame, struct cons_pointer env)
* (assoc key store)
* Returns the value associated with key in store, or NIL if not found.
*/
struct cons_pointer lisp_assoc( struct stack_frame* frame, struct cons_pointer env) {
return c_assoc( frame->arg[ 0], frame->arg[ 1]);
struct cons_pointer
lisp_assoc(struct stack_frame *frame, struct cons_pointer env)
{
return c_assoc(frame->arg[0], frame->arg[1]);
}
/**
* (eq a b)
* Returns T if a and b are pointers to the same object, else NIL
*/
struct cons_pointer lisp_eq( struct stack_frame* frame, struct cons_pointer env) {
return eq( frame->arg[ 0], frame->arg[ 1]) ? TRUE : NIL;
struct cons_pointer lisp_eq(struct stack_frame *frame, struct cons_pointer env)
{
return eq(frame->arg[0], frame->arg[1]) ? TRUE : NIL;
}
/**
* (eq a b)
* Returns T if a and b are pointers to structurally identical objects, else NIL
*/
struct cons_pointer lisp_equal( struct stack_frame* frame, struct cons_pointer env) {
return equal( frame->arg[ 0], frame->arg[ 1]) ? TRUE : NIL;
struct cons_pointer
lisp_equal(struct stack_frame *frame, struct cons_pointer env)
{
return equal(frame->arg[0], frame->arg[1]) ? TRUE : NIL;
}
/**
@ -298,14 +326,16 @@ struct cons_pointer lisp_equal( struct stack_frame* frame, struct cons_pointer e
* Read one complete lisp form and return it. If read-stream is specified and
* is a read stream, then read from that stream, else stdin.
*/
struct cons_pointer lisp_read( struct stack_frame* frame, struct cons_pointer env) {
FILE* input = stdin;
struct cons_pointer
lisp_read(struct stack_frame *frame, struct cons_pointer env)
{
FILE *input = stdin;
if ( readp( frame->arg[0])) {
input = pointer2cell( frame->arg[0]).payload.stream.stream;
if (readp(frame->arg[0])) {
input = pointer2cell(frame->arg[0]).payload.stream.stream;
}
return read( input);
return read(input);
}
/**
@ -314,27 +344,30 @@ struct cons_pointer lisp_read( struct stack_frame* frame, struct cons_pointer en
* Print one complete lisp form and return NIL. If write-stream is specified and
* is a write stream, then print to that stream, else stdout.
*/
struct cons_pointer lisp_print( struct stack_frame* frame, struct cons_pointer env) {
FILE* output = stdout;
struct cons_pointer
lisp_print(struct stack_frame *frame, struct cons_pointer env)
{
FILE *output = stdout;
if ( writep( frame->arg[1])) {
output = pointer2cell( frame->arg[1]).payload.stream.stream;
if (writep(frame->arg[1])) {
output = pointer2cell(frame->arg[1]).payload.stream.stream;
}
print( output, frame->arg[0]);
print(output, frame->arg[0]);
return NIL;
}
/**
* TODO: make this do something sensible somehow.
*/
struct cons_pointer lisp_throw( struct cons_pointer message, struct stack_frame* frame) {
fprintf( stderr, "\nERROR: ");
print( stderr, message);
fprintf( stderr, "\n\nAn exception was thrown and I've no idea what to do now\n");
struct cons_pointer
lisp_throw(struct cons_pointer message, struct stack_frame *frame)
{
fprintf(stderr, "\nERROR: ");
print(stderr, message);
fprintf(stderr,
"\n\nAn exception was thrown and I've no idea what to do now\n");
exit( 1);
exit(1);
}

54
src/lispops.h
View file

@ -19,23 +19,41 @@
* Licensed under GPL version 2.0, or, at your option, any later version.
*/
/* special forms */
struct cons_pointer lisp_eval( struct cons_pointer args, struct cons_pointer env,
struct stack_frame* frame);
struct cons_pointer lisp_apply( struct cons_pointer args, struct cons_pointer env,
struct stack_frame* frame);
struct cons_pointer lisp_quote( struct cons_pointer args, struct cons_pointer env,
struct stack_frame* frame);
/*
* special forms
*/
struct cons_pointer lisp_eval(struct cons_pointer args,
struct cons_pointer env,
struct stack_frame *frame);
struct cons_pointer lisp_apply(struct cons_pointer args,
struct cons_pointer env,
struct stack_frame *frame);
struct cons_pointer lisp_quote(struct cons_pointer args,
struct cons_pointer env,
struct stack_frame *frame);
/* functions */
struct cons_pointer lisp_cons( struct stack_frame* frame, struct cons_pointer env);
struct cons_pointer lisp_car( struct stack_frame* frame, struct cons_pointer env);
struct cons_pointer lisp_cdr( struct stack_frame* frame, struct cons_pointer env);
struct cons_pointer lisp_assoc( struct stack_frame* frame, struct cons_pointer env);
struct cons_pointer lisp_eq( struct stack_frame* frame, struct cons_pointer env);
struct cons_pointer lisp_equal( struct stack_frame* frame, struct cons_pointer env);
struct cons_pointer lisp_read( struct stack_frame* frame, struct cons_pointer env);
struct cons_pointer lisp_print( struct stack_frame* frame, struct cons_pointer env);
/*
* functions
*/
struct cons_pointer lisp_cons(struct stack_frame *frame,
struct cons_pointer env);
struct cons_pointer lisp_car(struct stack_frame *frame,
struct cons_pointer env);
struct cons_pointer lisp_cdr(struct stack_frame *frame,
struct cons_pointer env);
struct cons_pointer lisp_assoc(struct stack_frame *frame,
struct cons_pointer env);
struct cons_pointer lisp_eq(struct stack_frame *frame,
struct cons_pointer env);
struct cons_pointer lisp_equal(struct stack_frame *frame,
struct cons_pointer env);
struct cons_pointer lisp_read(struct stack_frame *frame,
struct cons_pointer env);
struct cons_pointer lisp_print(struct stack_frame *frame,
struct cons_pointer env);
/* neither, at this stage, really */
struct cons_pointer lisp_throw( struct cons_pointer message, struct stack_frame* frame);
/*
* neither, at this stage, really
*/
struct cons_pointer lisp_throw(struct cons_pointer message,
struct stack_frame *frame);

102
src/print.c
View file

@ -11,7 +11,9 @@
#include <ctype.h>
#include <stdio.h>
#include <string.h>
/* wide characters */
/*
* wide characters
*/
#include <wchar.h>
#include <wctype.h>
@ -20,86 +22,92 @@
#include "integer.h"
#include "print.h"
void print_string_contents( FILE* output, struct cons_pointer pointer) {
if ( stringp( pointer) || symbolp( pointer)) {
struct cons_space_object* cell = &pointer2cell(pointer);
void print_string_contents(FILE * output, struct cons_pointer pointer)
{
if (stringp(pointer) || symbolp(pointer)) {
struct cons_space_object *cell = &pointer2cell(pointer);
wint_t c = cell->payload.string.character;
if ( c != '\0') {
fputwc( c, output);
if (c != '\0') {
fputwc(c, output);
}
print_string_contents( output, cell->payload.string.cdr);
print_string_contents(output, cell->payload.string.cdr);
}
}
void print_string( FILE* output, struct cons_pointer pointer) {
fputwc( btowc('"'), output);
print_string_contents( output, pointer);
fputwc( btowc('"'), output);
void print_string(FILE * output, struct cons_pointer pointer)
{
fputwc(btowc('"'), output);
print_string_contents(output, pointer);
fputwc(btowc('"'), output);
}
/**
* Print a single list cell (cons cell). TODO: does not handle dotted pairs.
*/
void print_list_contents( FILE* output, struct cons_pointer pointer,
bool initial_space) {
struct cons_space_object* cell = &pointer2cell(pointer);
void
print_list_contents(FILE * output, struct cons_pointer pointer,
bool initial_space)
{
struct cons_space_object *cell = &pointer2cell(pointer);
switch ( cell->tag.value) {
case CONSTV :
switch (cell->tag.value) {
case CONSTV:
if (initial_space) {
fputwc( btowc(' '), output);
fputwc(btowc(' '), output);
}
print( output, cell->payload.cons.car);
print(output, cell->payload.cons.car);
print_list_contents( output, cell->payload.cons.cdr, true);
print_list_contents(output, cell->payload.cons.cdr, true);
break;
case NILTV:
break;
default:
fwprintf( output, L" . ");
print( output, pointer);
fwprintf(output, L" . ");
print(output, pointer);
}
}
void print_list( FILE* output, struct cons_pointer pointer) {
fputwc( btowc('('), output);
print_list_contents( output, pointer, false);
fputwc( btowc(')'), output);
void print_list(FILE * output, struct cons_pointer pointer)
{
fputwc(btowc('('), output);
print_list_contents(output, pointer, false);
fputwc(btowc(')'), output);
}
void print( FILE* output, struct cons_pointer pointer) {
struct cons_space_object cell = pointer2cell( pointer);
void print(FILE * output, struct cons_pointer pointer)
{
struct cons_space_object cell = pointer2cell(pointer);
/* Because tags have values as well as bytes, this if ... else if
* statement can ultimately be replaced by a switch, which will
* be neater. */
switch ( cell.tag.value) {
case CONSTV :
print_list( output, pointer);
/*
* Because tags have values as well as bytes, this if ... else if
* statement can ultimately be replaced by a switch, which will be neater.
*/
switch (cell.tag.value) {
case CONSTV:
print_list(output, pointer);
break;
case INTEGERTV :
fwprintf( output, L"%ld", cell.payload.integer.value);
case INTEGERTV:
fwprintf(output, L"%ld", cell.payload.integer.value);
break;
case NILTV :
fwprintf( output, L"nil");
case NILTV:
fwprintf(output, L"nil");
break;
case REALTV:
fwprintf(output, L"%lf", cell.payload.real.value);
break;
case STRINGTV :
print_string( output, pointer);
case STRINGTV:
print_string(output, pointer);
break;
case SYMBOLTV :
print_string_contents( output, pointer);
case SYMBOLTV:
print_string_contents(output, pointer);
break;
case TRUETV :
fwprintf( output, L"t");
case TRUETV:
fwprintf(output, L"t");
break;
default :
fwprintf( stderr, L"Error: Unrecognised tag value %d (%c%c%c%c)\n",
default:
fwprintf(stderr,
L"Error: Unrecognised tag value %d (%c%c%c%c)\n",
cell.tag.value, cell.tag.bytes[0], cell.tag.bytes[1],
cell.tag.bytes[2], cell.tag.bytes[3]);
break;

2
src/print.h
View file

@ -14,6 +14,6 @@
#ifndef __print_h
#define __print_h
void print( FILE* output, struct cons_pointer pointer);
void print(FILE * output, struct cons_pointer pointer);
#endif

167
src/read.c
View file

@ -11,7 +11,9 @@
#include <math.h>
#include <stdbool.h>
#include <stdio.h>
/* wide characters */
/*
* wide characters
*/
#include <wchar.h>
#include <wctype.h>
@ -21,23 +23,23 @@
#include "read.h"
#include "real.h"
/* for the time being things which may be read are:
strings
numbers - either integer or real, but not yet including ratios or bignums
lists
Can't read atoms because I don't yet know what an atom is or how it's stored. */
/*
* for the time being things which may be read are: strings numbers - either
* integer or real, but not yet including ratios or bignums lists Can't read
* atoms because I don't yet know what an atom is or how it's stored.
*/
struct cons_pointer read_number( FILE* input, wint_t initial);
struct cons_pointer read_list( FILE* input, wint_t initial);
struct cons_pointer read_string( FILE* input, wint_t initial);
struct cons_pointer read_symbol( FILE* input, wint_t initial);
struct cons_pointer read_number(FILE * input, wint_t initial);
struct cons_pointer read_list(FILE * input, wint_t initial);
struct cons_pointer read_string(FILE * input, wint_t initial);
struct cons_pointer read_symbol(FILE * input, wint_t initial);
/**
* quote reader macro in C (!)
*/
struct cons_pointer c_quote( struct cons_pointer arg) {
return make_cons( c_string_to_lisp_symbol( "quote"),
make_cons( arg, NIL));
struct cons_pointer c_quote(struct cons_pointer arg)
{
return make_cons(c_string_to_lisp_symbol("quote"), make_cons(arg, NIL));
}
/**
@ -45,94 +47,93 @@ struct cons_pointer c_quote( struct cons_pointer arg) {
* treating this initial character as the first character of the object
* representation.
*/
struct cons_pointer read_continuation( FILE* input, wint_t initial) {
struct cons_pointer read_continuation(FILE * input, wint_t initial)
{
struct cons_pointer result = NIL;
wint_t c;
for (c = initial;
c == '\0' || iswblank( c) || iswcntrl(c);
c = fgetwc( input));
c == '\0' || iswblank(c) || iswcntrl(c); c = fgetwc(input));
switch( c) {
switch (c) {
case '\'':
result = c_quote( read_continuation( input, fgetwc( input)));
result = c_quote(read_continuation(input, fgetwc(input)));
break;
case '(' :
result = read_list(input, fgetwc( input));
case '(':
result = read_list(input, fgetwc(input));
break;
case '"':
result = read_string(input, fgetwc( input));
result = read_string(input, fgetwc(input));
break;
default:
if ( iswdigit( c)) {
result = read_number( input, c);
} else if (iswprint( c)) {
result = read_symbol( input, c);
if (iswdigit(c)) {
result = read_number(input, c);
} else if (iswprint(c)) {
result = read_symbol(input, c);
} else {
fprintf( stderr, "Unrecognised start of input character %c\n", c);
fprintf(stderr, "Unrecognised start of input character %c\n", c);
}
}
return result;
}
/**
* read a number from this input stream, given this initial character.
*/
struct cons_pointer read_number( FILE* input, wint_t initial) {
struct cons_pointer read_number(FILE * input, wint_t initial)
{
int accumulator = 0;
int places_of_decimals = 0;
bool seen_period = false;
wint_t c;
fprintf( stderr, "read_number starting '%c' (%d)\n", initial, initial);
fprintf(stderr, "read_number starting '%c' (%d)\n", initial, initial);
for (c = initial; iswdigit( c) || c == btowc('.'); c = fgetwc( input)) {
if ( c == btowc('.')) {
for (c = initial; iswdigit(c) || c == btowc('.'); c = fgetwc(input)) {
if (c == btowc('.')) {
seen_period = true;
} else {
accumulator = accumulator * 10 + ((int)c - (int)'0');
accumulator = accumulator * 10 + ((int) c - (int) '0');
if ( seen_period) {
places_of_decimals ++;
if (seen_period) {
places_of_decimals++;
}
}
}
/* push back the character read which was not a digit */
ungetwc( c, input);
/*
* push back the character read which was not a digit
*/
ungetwc(c, input);
if (seen_period) {
return make_real(accumulator / pow(10, places_of_decimals));
}
else
{
return make_integer( accumulator);
} else {
return make_integer(accumulator);
}
}
/**
* Read a list from this input stream, which no longer contains the opening
* left parenthesis.
*/
struct cons_pointer read_list( FILE* input, wint_t initial) {
struct cons_pointer result= NIL;
struct cons_pointer read_list(FILE * input, wint_t initial)
{
struct cons_pointer result = NIL;
if ( initial != ')' ) {
fwprintf( stderr, L"read_list starting '%C' (%d)\n", initial, initial);
struct cons_pointer car = read_continuation( input, initial);
result = make_cons( car, read_list( input, fgetwc( input)));
if (initial != ')') {
fwprintf(stderr, L"read_list starting '%C' (%d)\n", initial, initial);
struct cons_pointer car = read_continuation(input, initial);
result = make_cons(car, read_list(input, fgetwc(input)));
} else {
fprintf( stderr, "End of list detected\n");
fprintf(stderr, "End of list detected\n");
}
return result;
}
/**
* Read a string. This means either a string delimited by double quotes
* (is_quoted == true), in which case it may contain whitespace but may
@ -140,57 +141,64 @@ struct cons_pointer read_list( FILE* input, wint_t initial) {
* so delimited in which case it may not contain whitespace (unless escaped)
* but may contain a double quote character (probably not a good idea!)
*/
struct cons_pointer read_string( FILE* input, wint_t initial) {
struct cons_pointer read_string(FILE * input, wint_t initial)
{
struct cons_pointer cdr = NIL;
struct cons_pointer result;
fwprintf( stderr, L"read_string starting '%C' (%d)\n",
initial, initial);
fwprintf(stderr, L"read_string starting '%C' (%d)\n", initial, initial);
switch ( initial) {
switch (initial) {
case '\0':
result = make_string( initial, NIL);
result = make_string(initial, NIL);
break;
case '"':
result = make_string( '\0', NIL);
result = make_string('\0', NIL);
break;
default:
result = make_string( initial, read_string( input, fgetwc( input)));
result = make_string(initial, read_string(input, fgetwc(input)));
break;
}
return result;
}
struct cons_pointer read_symbol( FILE* input, wint_t initial) {
struct cons_pointer read_symbol(FILE * input, wint_t initial)
{
struct cons_pointer cdr = NIL;
struct cons_pointer result;
fwprintf( stderr, L"read_symbol starting '%C' (%d)\n",
initial, initial);
fwprintf(stderr, L"read_symbol starting '%C' (%d)\n", initial, initial);
switch ( initial) {
switch (initial) {
case '\0':
result = make_symbol( initial, NIL);
result = make_symbol(initial, NIL);
break;
case '"':
/* THIS IS NOT A GOOD IDEA, but is legal */
result = make_symbol( initial, read_symbol( input, fgetwc( input)));
/*
* THIS IS NOT A GOOD IDEA, but is legal
*/
result = make_symbol(initial, read_symbol(input, fgetwc(input)));
break;
case ')' :
/* unquoted strings may not include right-parenthesis */
result = make_symbol( '\0', NIL);
/* push back the character read */
ungetwc( initial, input);
case ')':
/*
* unquoted strings may not include right-parenthesis
*/
result = make_symbol('\0', NIL);
/*
* push back the character read
*/
ungetwc(initial, input);
break;
default:
if ( iswblank( initial) || !iswprint( initial)) {
result = make_symbol( '\0', NIL);
/* push back the character read */
ungetwc( initial, input);
if (iswblank(initial) || !iswprint(initial)) {
result = make_symbol('\0', NIL);
/*
* push back the character read
*/
ungetwc(initial, input);
} else {
result = make_symbol( initial, read_symbol( input, fgetwc( input)));
result = make_symbol(initial, read_symbol(input, fgetwc(input)));
}
break;
}
@ -198,15 +206,10 @@ struct cons_pointer read_symbol( FILE* input, wint_t initial) {
return result;
}
/**
* Read the next object on this input stream and return a cons_pointer to it.
*/
struct cons_pointer read( FILE* input) {
return read_continuation( input, fgetwc( input));
struct cons_pointer read(FILE * input)
{
return read_continuation(input, fgetwc(input));
}

2
src/read.h
View file

@ -14,6 +14,6 @@
/**
* read the next object on this input stream and return a cons_pointer to it.
*/
struct cons_pointer read( FILE* input);
struct cons_pointer read(FILE * input);
#endif

8
src/real.c
View file

@ -14,11 +14,11 @@
* @param value the value to wrap;
* @return a real number cell wrapping this value.
*/
struct cons_pointer make_real( long double value) {
struct cons_pointer result = allocate_cell( REALTAG);
struct cons_space_object* cell = &pointer2cell(result);
struct cons_pointer make_real(long double value)
{
struct cons_pointer result = allocate_cell(REALTAG);
struct cons_space_object *cell = &pointer2cell(result);
cell->payload.real.value = value;
return result;
}

5
src/real.h
View file

@ -24,12 +24,9 @@ extern "C" {
* @param value the value to wrap;
* @return a real number cell wrapping this value.
*/
struct cons_pointer make_real( double value);
struct cons_pointer make_real(double value);
#ifdef __cplusplus
}
#endif
#endif /* REAL_H */

24
src/repl.c
View file

@ -21,22 +21,22 @@
* @param err_stream the stream to send errors to;
* @param show_prompt true if prompts should be shown.
*/
void repl( FILE* in_stream, FILE* out_stream, FILE* error_stream,
bool show_prompt) {
void
repl(FILE * in_stream, FILE * out_stream, FILE * error_stream,
bool show_prompt)
{
while (!feof(in_stream)) {
if (show_prompt) {
fwprintf( out_stream, L"\n:: ");
fwprintf(out_stream, L"\n:: ");
}
struct cons_pointer input = read( in_stream);
fwprintf( error_stream, L"\nread {%d,%d}=> ", input.page, input.offset);
struct cons_pointer input = read(in_stream);
fwprintf(error_stream, L"\nread {%d,%d}=> ", input.page, input.offset);
if (show_prompt) {
fwprintf( out_stream, L"\n-> ");
fwprintf(out_stream, L"\n-> ");
}
// print( out_stream, lisp_eval(input, oblist, NULL));
print( out_stream, input);
fwprintf( out_stream, L"\n");
fwprintf( error_stream, L"\neval {%d,%d}=> ", input.page, input.offset);
// print( out_stream, lisp_eval(input, oblist, NULL));
print(out_stream, input);
fwprintf(out_stream, L"\n");
fwprintf(error_stream, L"\neval {%d,%d}=> ", input.page, input.offset);
}
}

7
src/repl.h
View file

@ -25,13 +25,10 @@ extern "C" {
* @param err_stream the stream to send errors to;
* @param show_prompt true if prompts should be shown.
*/
void repl( FILE* in_stream, FILE* out_stream, FILE* error_stream,
bool show_prompt);
void repl(FILE * in_stream, FILE * out_stream,
FILE * error_stream, bool show_prompt);
#ifdef __cplusplus
}
#endif
#endif /* REPL_H */

81
src/stack.c
View file

@ -29,44 +29,53 @@
* Allocate a new stack frame with its previous pointer set to this value,
* its arguments set up from these args, evaluated in this env.
*/
struct stack_frame* make_stack_frame( struct stack_frame* previous,
struct stack_frame *make_stack_frame(struct stack_frame *previous,
struct cons_pointer args,
struct cons_pointer env) {
/* TODO: later, pop a frame off a free-list of stack frames */
struct stack_frame* result = malloc( sizeof( struct stack_frame));
struct cons_pointer env)
{
/*
* TODO: later, pop a frame off a free-list of stack frames
*/
struct stack_frame *result = malloc(sizeof(struct stack_frame));
result->previous = previous;
/* clearing the frame with memset would probably be slightly quicker, but
* this is clear. */
/*
* clearing the frame with memset would probably be slightly quicker, but
* this is clear.
*/
result->more = NIL;
result->function = NIL;
for ( int i = 0; i < args_in_frame; i++) {
for (int i = 0; i < args_in_frame; i++) {
result->arg[i] = NIL;
}
int i = 0; /* still an index into args, so same
* name will do */
int i = 0; /* still an index into args, so same name will
* do */
while ( ! nilp( args)) { /* iterate down the arg list filling in
* the arg slots in the frame. When there
* are no more slots, if there are still
* args, stash them on more */
struct cons_space_object cell = pointer2cell( args);
while (!nilp(args)) { /* iterate down the arg list filling in the
* arg slots in the frame. When there are no
* more slots, if there are still args, stash
* them on more */
struct cons_space_object cell = pointer2cell(args);
if ( i < args_in_frame) {
/* TODO: if we were running on real massively parallel hardware, each
* arg except the first should be handed off to another processor to
* be evaled in parallel */
result->arg[i] = lisp_eval( cell.payload.cons.car, env, result);
inc_ref( result->arg[i]);
if (i < args_in_frame) {
/*
* TODO: if we were running on real massively parallel hardware,
* each arg except the first should be handed off to another
* processor to be evaled in parallel
*/
result->arg[i] = lisp_eval(cell.payload.cons.car, env, result);
inc_ref(result->arg[i]);
args = cell.payload.cons.cdr;
} else {
/* TODO: this isn't right. These args should also each be evaled. */
/*
* TODO: this isn't right. These args should also each be evaled.
*/
result->more = args;
inc_ref( result->more);
inc_ref(result->more);
args = NIL;
}
@ -78,32 +87,36 @@ struct stack_frame* make_stack_frame( struct stack_frame* previous,
/**
* Free this stack frame.
*/
void free_stack_frame( struct stack_frame* frame) {
/* TODO: later, push it back on the stack-frame freelist */
for ( int i = 0; i < args_in_frame; i++) {
dec_ref( frame->arg[ i]);
void free_stack_frame(struct stack_frame *frame)
{
/*
* TODO: later, push it back on the stack-frame freelist
*/
for (int i = 0; i < args_in_frame; i++) {
dec_ref(frame->arg[i]);
}
dec_ref( frame->more);
dec_ref(frame->more);
free( frame);
free(frame);
}
/**
* Fetch a pointer to the value of the local variable at this index.
*/
struct cons_pointer fetch_arg( struct stack_frame* frame, unsigned int index) {
struct cons_pointer fetch_arg(struct stack_frame *frame, unsigned int index)
{
struct cons_pointer result = NIL;
if ( index < args_in_frame) {
result = frame->arg[ index];
if (index < args_in_frame) {
result = frame->arg[index];
} else {
struct cons_pointer p = frame->more;
for ( int i = args_in_frame; i < index; i++) {
p = pointer2cell( p).payload.cons.cdr;
for (int i = args_in_frame; i < index; i++) {
p = pointer2cell(p).payload.cons.cdr;
}
result = pointer2cell( p).payload.cons.car;
result = pointer2cell(p).payload.cons.car;
}
return result;

12
src/stack.h
View file

@ -24,13 +24,15 @@
#ifndef __stack_h
#define __stack_h
struct stack_frame* make_stack_frame( struct stack_frame* previous,
struct stack_frame *make_stack_frame(struct stack_frame *previous,
struct cons_pointer args,
struct cons_pointer env);
void free_stack_frame( struct stack_frame* frame);
struct cons_pointer fetch_arg( struct stack_frame* frame, unsigned int n);
void free_stack_frame(struct stack_frame *frame);
struct cons_pointer fetch_arg(struct stack_frame *frame, unsigned int n);
/* struct stack_frame is defined in consspaceobject.h to break circularity
* TODO: refactor. */
/*
* struct stack_frame is defined in consspaceobject.h to break circularity
* TODO: refactor.
*/
#endif

1
src/version.h
View file

@ -8,5 +8,4 @@
* Licensed under GPL version 2.0, or, at your option, any later version.
*/
#define VERSION "0.0.0"