musl/src/stdio/fopen.c

35 lines
666 B
C

#include "stdio_impl.h"
FILE *fopen(const char *filename, const char *mode)
{
FILE *f;
int fd;
int flags;
int plus = !!strchr(mode, '+');
/* Check for valid initial mode character */
if (!strchr("rwa", *mode)) {
errno = EINVAL;
return 0;
}
/* Compute the flags to pass to open() */
if (plus) flags = O_RDWR;
else if (*mode == 'r') flags = O_RDONLY;
else flags = O_WRONLY;
if (*mode != 'r') flags |= O_CREAT;
if (*mode == 'w') flags |= O_TRUNC;
if (*mode == 'a') flags |= O_APPEND;
fd = __syscall_open(filename, flags, 0666);
if (fd < 0) return 0;
f = __fdopen(fd, mode);
if (f) return f;
__syscall_close(fd);
return 0;
}
LFS64(fopen);