rt-thread/components/libc/posix/getline/posix_getline.c

79 lines
1.9 KiB
C

/* posix_getline.c
* RT-Thread POSIX
* getdelim(), getline() - read a delimited record from stream, ersatz implementation
* This code is unlicensed -- free and released into the public domain.
* https://man7.org/linux/man-pages/man3/getline.3.html
* Authors:
* https://github.com/ivanrad/getline
*
* Meco Man 2020-09-03 porting to RT-Thread
*/
#include "posix_getline.h"
#include <stdlib.h>
#include <limits.h>
#include <sys/errno.h>
ssize_t getdelim(char **lineptr, size_t *n, int delim, FILE *stream) {
char *cur_pos, *new_lineptr;
size_t new_lineptr_len;
int c;
if (lineptr == NULL || n == NULL || stream == NULL) {
errno = EINVAL;
return -1;
}
if (*lineptr == NULL) {
*n = 128; /* init len */
if ((*lineptr = (char *)malloc(*n)) == NULL) {
errno = ENOMEM;
return -1;
}
}
cur_pos = *lineptr;
for (;;) {
c = getc(stream);
if (ferror(stream) || (c == EOF && cur_pos == *lineptr))
return -1;
if (c == EOF)
break;
if ((*lineptr + *n - cur_pos) < 2) {
if (LONG_MAX / 2 < *n) {
#ifdef EOVERFLOW
errno = EOVERFLOW;
#else
errno = ERANGE; /* no EOVERFLOW defined */
#endif
return -1;
}
new_lineptr_len = *n * 2;
if ((new_lineptr = (char *)realloc(*lineptr, new_lineptr_len)) == NULL) {
errno = ENOMEM;
return -1;
}
cur_pos = new_lineptr + (cur_pos - *lineptr);
*lineptr = new_lineptr;
*n = new_lineptr_len;
}
*cur_pos++ = (char)c;
if (c == delim)
break;
}
*cur_pos = '\0';
return (ssize_t)(cur_pos - *lineptr);
}
ssize_t getline(char **lineptr, size_t *n, FILE *stream) {
return getdelim(lineptr, n, '\n', stream);
}