segatools/util/slurp.c

67 lines
1.5 KiB
C

#include <stdbool.h>
#include <stdio.h>
#include <stdlib.h>
/*
* 'slurp' reads the file identified by 'path' into a character buffer
* pointed at by 'buf', optionally adding a terminating NUL if
* 'add_nul' is true. On success, the size of the file is returned; on
* failure, -1 is returned and ERRNO is set by the underlying system
* or library call that failed.
*
* WARNING: 'slurp' malloc()s memory to '*buf' which must be freed by
* the caller.
*/
long wslurp(const wchar_t* path, char **buf, bool add_nul)
{
FILE *fp;
size_t fsz;
long off_end;
int rc;
/* Open the file */
fp = _wfopen(path, L"rb");
if( NULL == fp ) {
return -1L;
}
/* Seek to the end of the file */
rc = fseek(fp, 0L, SEEK_END);
if( 0 != rc ) {
return -1L;
}
/* Byte offset to the end of the file (size) */
if( 0 > (off_end = ftell(fp)) ) {
return -1L;
}
fsz = (size_t)off_end;
/* Allocate a buffer to hold the whole file */
*buf = malloc( fsz+(int)add_nul );
if( NULL == *buf ) {
return -1L;
}
/* Rewind file pointer to start of file */
rewind(fp);
/* Slurp file into buffer */
if( fsz != fread(*buf, 1, fsz, fp) ) {
free(*buf);
return -1L;
}
/* Close the file */
if( EOF == fclose(fp) ) {
free(*buf);
return -1L;
}
if( add_nul ) {
/* Make sure the buffer is NUL-terminated, just in case */
buf[fsz] = '\0';
}
/* Return the file size */
return (long)fsz;
}