hush/libbb/fgets_str.c

65 lines
1.7 KiB
C

/*
* This program is free software; you can redistribute it and/or modify
* it under the terms of the GNU General Public License as published by
* the Free Software Foundation; either version 2 of the License, or
* (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Library General Public License for more details.
*
* You should have received a copy of the GNU General Public License
* along with this program; if not, write to the Free Software
* Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
/*
* Continue reading from file until the terminating string is encountered.
* Return data as string.
* e.g. fgets_str(file, "\n"); will read till end of file
*/
char *fgets_str(FILE *file, const char *terminating_string)
{
char *linebuf = NULL;
const int term_length = strlen(terminating_string);
int end_string_offset;
int linebufsz = 0;
int idx = 0;
int ch;
while (1) {
ch = fgetc(file);
if (ch == EOF) {
break;
}
/* grow the line buffer as necessary */
while (idx > linebufsz - 2) {
linebuf = realloc(linebuf, linebufsz += 1000); /* GROWBY */
}
linebuf[idx] = ch;
idx++;
/* Check for terminating string */
end_string_offset = idx - term_length;
if ((end_string_offset > 0) && (memcmp(&linebuf[end_string_offset], terminating_string, term_length) == 0)) {
idx -= term_length;
break;
}
}
if (idx == 0) {
return NULL;
}
linebuf[idx] = '\0';
return(linebuf);
}