interpret/src/text.c

48 lines
1.7 KiB
C

/** Dynamic contiguous string that is used to load files. */
#define ARRAY_NAME char
#define ARRAY_TYPE char
#include "../src/array.h"
#define HAVE_CHAR_ARRAY
#include "text.h"
#include <stdio.h>
/** Append a text file, `fn`, to `c`, and add a '\0'.
@return The start of the appended file or null on error. A partial read is a
failure. @throws[fopen, fread, malloc]
@throws[EISEQ] The text file has embedded nulls.
@throws[ERANGE] If the standard library does not follow POSIX. */
static char *append_file(struct char_array *text, const char *const fn) {
FILE *fp = 0;
const size_t granularity = 1024;
size_t nread, start;
char *cursor;
int success = 1;
assert(text && fn);
start = text->size;
if(!(fp = fopen(fn, "r"))) goto catch;
/* Read entire file in chunks. */
do if(!(cursor = char_array_buffer(text, granularity))
|| (nread = fread(cursor, 1, granularity, fp), ferror(fp))
|| !char_array_append(text, nread)) goto catch;
while(nread == granularity);
/* File to `C` string. */
if(!(cursor = char_array_new(text))) goto catch;
*cursor = '\0';
/* Binary files with embedded '\0' are not allowed; check just this read. */
if(strchr(text->data + start, '\0') != cursor)
{ errno = EILSEQ; goto catch; }
goto finally;
catch:
if(!errno) errno = EILSEQ; /* Will never be true on POSIX. */
success = 0;
finally:
if(fp) fclose(fp);
return success ? text->data + start : 0;
}
struct text text(void) { struct text text; text.a = char_array(); return text; }
void text_(struct text *const text) { printf("~text: errno %d text.a.data %p\n", errno, (void *)text->a.data); char_array_(&text->a); printf("~text: errno %d\n", errno); }
char *text_append_file(struct text *text, const char *const fn)
{ return append_file(&text->a, fn); }