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#include "__stdio.h" // for __FILE, __libc_fadd
#include "features.h" // for __weak
#include "stdatomic.h" // for atomic_flag_clear
#include "stddef.h" // for NULL
#include <errno.h> // for EINVAL, errno
#include <fcntl.h> // for O_WRONLY, O_CREAT, O_RDONLY, open, O_APPEND
#include <stdio.h> // for FILE, BUFSIZ, fopen, _IOLBF
#include <stdlib.h> // for calloc, free, malloc
#include <string.h> // for strchr
#include <unistd.h> // for close
__weak void __stdio_cleanup(void)
{
}
FILE *fopen(const char *restrict pathname, const char *restrict mode)
{
int fd, flags, _mode;
FILE *stream;
_mode = 0;
if (mode[0] == 'r') {
flags = O_RDONLY;
} else if (mode[0] == 'w') {
flags = O_WRONLY | O_CREAT | O_TRUNC;
} else if (mode[0] == 'a') {
flags = O_WRONLY | O_CREAT | O_APPEND;
_mode = 0666;
} else {
errno = EINVAL;
return NULL;
}
if (strchr(mode, '+')) {
flags = (flags & ~(O_RDONLY | O_WRONLY)) | O_RDWR;
}
if ((fd = open(pathname, flags, _mode)) < 0)
return NULL;
if ((stream = calloc(1, sizeof(FILE))) == NULL)
return NULL;
__FILE(stream)->fd = fd;
__FILE(stream)->buf_size = BUFSIZ;
__FILE(stream)->flags = flags;
__FILE(stream)->type = _IOLBF;
atomic_flag_clear(&__FILE(stream)->lock);
if ((__FILE(stream)->buf = malloc(BUFSIZ)) == NULL) {
close(fd);
free(stream);
return NULL;
}
__libc_fadd(stream);
return stream;
}
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