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Metadata for file streams

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This commit is contained in:
Simon Brooke 2019-01-31 13:24:06 +00:00
parent 5e1ec1181a
commit bd4d655362
2 changed files with 82 additions and 63 deletions

137
src/io/io.c
View file

@ -10,11 +10,15 @@
* Licensed under GPL version 2.0, or, at your option, any later version.
*/
#include <grp.h>
#include <langinfo.h>
#include <pwd.h>
#include <stdlib.h>
#include <string.h>
#include <sys/stat.h>
#include <sys/types.h>
#include <unistd.h>
#include <uuid/uuid.h>
/*
* wide characters
*/
@ -270,29 +274,33 @@ char *trim( char *s ) {
}
void maybe_add_status_meta(struct cons_space_object *cell) {
struct cons_pointer status_key = c_string_to_lisp_keyword( L"status-code" );
debug_print(L"maybe_add_status_meta: entered\n", DEBUG_IO);
if (cell->payload.stream.stream->type == CFTYPE_CURL &&
nilp(c_assoc( status_key, cell->payload.stream.meta))) {
long status = 0;
curl_easy_getinfo(cell->payload.stream.stream->handle.curl,
CURLINFO_RESPONSE_CODE,
&status);
debug_printf( DEBUG_IO, L"maybe_add_status_meta: read HTTP status %d\n", status);
if (status > 0) {
cell->payload.stream.meta = make_cons(
make_cons(status_key,
make_integer(status, NIL)),
cell->payload.stream.meta);
}
}
struct cons_pointer add_meta_integer( struct cons_pointer meta, wchar_t *key,
long int value ) {
return
make_cons( make_cons
( c_string_to_lisp_keyword( key ),
make_integer( value, NIL ) ), meta );
}
struct cons_pointer add_meta_string( struct cons_pointer meta, wchar_t *key,
char *value ) {
wchar_t buffer[strlen( value ) + 1];
mbstowcs( buffer, value, strlen( value ) );
return make_cons( make_cons( c_string_to_lisp_keyword( key ),
c_string_to_lisp_string( buffer ) ), meta );
}
struct cons_pointer add_meta_time( struct cons_pointer meta, wchar_t *key,
time_t * value ) {
/* I don't yet have a concept of a date-time object, which is a
* bit of an oversight! */
char datestring[256];
struct tm *tm = localtime( value );
strftime( datestring, sizeof( datestring ), nl_langinfo( D_T_FMT ), tm );
return add_meta_string( meta, key, datestring );
}
/**
* Callback to assemble metadata for a URL stream. This is naughty because
@ -303,9 +311,9 @@ static size_t write_meta_callback( char *string, size_t size, size_t nmemb,
struct cons_space_object *cell = &pointer2cell( stream );
/* make a copy of the string that we can destructively change */
char * s = calloc(strlen(string), sizeof(char));
char *s = calloc( strlen( string ), sizeof( char ) );
strcpy( s, string);
strcpy( s, string );
if ( strncmp( &cell->tag.bytes[0], READTAG, 4 ) ||
strncmp( &cell->tag.bytes[0], WRITETAG, 4 ) ) {
@ -315,37 +323,26 @@ static size_t write_meta_callback( char *string, size_t size, size_t nmemb,
s[offset] = ( char ) 0;
char *name = trim( s );
char *value = trim( &s[++offset] );
wchar_t *wname = calloc( strlen( name ), sizeof( wchar_t ) );
wchar_t *wvalue = calloc( strlen( value ), sizeof( wchar_t ) );
wchar_t wname[strlen( name )];
mbstowcs( wname, name, strlen( name ) );
mbstowcs( wvalue, value, strlen( value ) );
cell->payload.stream.meta =
make_cons( make_cons
( c_string_to_lisp_keyword( wname ),
c_string_to_lisp_string( wvalue ) ),
cell->payload.stream.meta );
free(wname);
free(wvalue);
add_meta_string( cell->payload.stream.meta, wname, value );
debug_printf( DEBUG_IO,
L"write_meta_callback: added header '%s': value '%s'\n",
name, value );
} else if (strncmp( "HTTP", s, 4) == 0) {
} else if ( strncmp( "HTTP", s, 4 ) == 0 ) {
int offset = index_of( ' ', s );
char *value = trim( &s[offset] );
wchar_t *wvalue = calloc( strlen( value ), sizeof( wchar_t ) );
mbstowcs( wvalue, value, strlen( value ) );
cell->payload.stream.meta =
make_cons( make_cons
( c_string_to_lisp_keyword( L"status" ),
c_string_to_lisp_string( wvalue ) ),
cell->payload.stream.meta );
maybe_add_status_meta( cell);
add_meta_integer( add_meta_string
( cell->payload.stream.meta, L"status",
value ), L"status-code", strtol( value,
NULL,
10 ) );
debug_printf( DEBUG_IO,
L"write_meta_callback: added header 'status': value '%s'\n",
@ -355,27 +352,54 @@ static size_t write_meta_callback( char *string, size_t size, size_t nmemb,
L"write_meta_callback: header passed with no colon: '%s'\n",
s );
}
} else {
} else {
debug_print
( L"Pointer passed to write_meta_callback did not point to a stream: ",
DEBUG_IO );
debug_dump_object( stream, DEBUG_IO );
}
free(s);
return strlen(string);
free( s );
return strlen( string );
}
void collect_meta( struct cons_pointer stream, struct cons_pointer url ) {
void collect_meta( struct cons_pointer stream, char *url ) {
struct cons_space_object *cell = &pointer2cell( stream );
URL_FILE *s = pointer2cell( stream ).payload.stream.stream;
struct cons_pointer meta =
add_meta_string( cell->payload.stream.meta, L"url", url );
struct stat statbuf;
int result = stat( url, &statbuf );
struct passwd *pwd;
struct group *grp;
switch ( s->type ) {
case CFTYPE_NONE:
break;
case CFTYPE_FILE:
/* don't know whether you can get metadata on an open stream in C,
* although we could of course get it from the URL */
if ( result == 0 ) {
if ( ( pwd = getpwuid( statbuf.st_uid ) ) != NULL ) {
meta = add_meta_string( meta, L"owner", pwd->pw_name );
} else {
meta = add_meta_integer( meta, L"owner", statbuf.st_uid );
}
if ( ( grp = getgrgid( statbuf.st_gid ) ) != NULL ) {
meta = add_meta_string( meta, L"group", grp->gr_name );
} else {
meta = add_meta_integer( meta, L"group", statbuf.st_gid );
}
meta =
add_meta_integer( meta, L"size",
( intmax_t ) statbuf.st_size );
meta = add_meta_time( meta, L"modified", &statbuf.st_mtime );
/* this is destructive change before the cell is released into the
* wild, and consequently permissible, just. */
cell->payload.stream.meta = meta;
}
break;
case CFTYPE_CURL:
curl_easy_setopt( s->handle.curl, CURLOPT_VERBOSE, 1L );
@ -409,26 +433,21 @@ lisp_open( struct stack_frame *frame, struct cons_pointer frame_pointer,
struct cons_pointer result = NIL;
if ( stringp( frame->arg[0] ) ) {
struct cons_pointer meta =
make_cons(make_cons( c_string_to_lisp_keyword( L"url" ),
frame->arg[0] ),
NIL );
char *url = lisp_string_to_c_string( frame->arg[0] );
if ( nilp( frame->arg[1] ) ) {
URL_FILE *stream = url_fopen( url, "r" );
result = make_read_stream( stream, meta );
result = make_read_stream( stream, NIL );
} else {
// TODO: anything more complex is a problem for another day.
URL_FILE *stream = url_fopen( url, "w" );
result = make_write_stream( stream, meta );
result = make_write_stream( stream, NIL );
}
if ( pointer2cell( result ).payload.stream.stream == NULL ) {
result = NIL;
} else {
collect_meta( result, frame->arg[0] );
collect_meta( result, url );
}
free( url );
@ -457,8 +476,8 @@ lisp_read_char( struct stack_frame *frame, struct cons_pointer frame_pointer,
if ( readp( frame->arg[0] ) ) {
result =
make_string( url_fgetwc
( pointer2cell( frame->arg[0] ).payload.stream.
stream ), NIL );
( pointer2cell( frame->arg[0] ).payload.
stream.stream ), NIL );
}
return result;

8
src/ops/lispops.c
View file

@ -646,12 +646,12 @@ lisp_car( struct stack_frame *frame, struct cons_pointer frame_pointer,
case CONSTV:
result = cell.payload.cons.car;
break;
case NILTV:
break;
case READTV:
result =
make_string( url_fgetwc( cell.payload.stream.stream ), NIL );
break;
case NILTV:
break;
case STRINGTV:
result = make_string( cell.payload.string.character, NIL );
break;
@ -690,6 +690,8 @@ lisp_cdr( struct stack_frame *frame, struct cons_pointer frame_pointer,
case CONSTV:
result = cell.payload.cons.cdr;
break;
case NILTV:
break;
case READTV:
url_fgetwc( cell.payload.stream.stream );
result = frame->arg[0];
@ -697,8 +699,6 @@ lisp_cdr( struct stack_frame *frame, struct cons_pointer frame_pointer,
case STRINGTV:
result = cell.payload.string.cdr;
break;
case NILTV:
break;
default:
result =
throw_exception( c_string_to_lisp_string