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#include "__stdio.h" // for __FILE, _IO_EOF, _IO_ERR
#include <atomic.h> // for LIBC_LOCK, LIBC_UNLOCK
#include <stdio.h> // for fread, BUFSIZ, FILE
#include <string.h> // for memcpy
#include <unistd.h> // for size_t, read, ssize_t
char __stdin_buffer[BUFSIZ];
size_t fread(void *restrict ptr, size_t size, size_t nitems,
FILE *restrict stream)
{
if (size == 0 || nitems == 0)
return 0;
size_t total = size * nitems;
size_t bytes_read = 0;
char *p = ptr;
LIBC_LOCK(__FILE(stream)->lock);
while (total > 0) {
if (__FILE(stream)->buf_pos < __FILE(stream)->buf_len) {
size_t available = __FILE(stream)->buf_len -
__FILE(stream)->buf_pos;
size_t to_copy = total < available ? total : available;
memcpy(p, __FILE(stream)->buf + __FILE(stream)->buf_pos,
to_copy);
__FILE(stream)->buf_pos += to_copy;
p += to_copy;
bytes_read += to_copy;
total -= to_copy;
continue;
}
ssize_t ret = read(__FILE(stream)->fd, __FILE(stream)->buf,
__FILE(stream)->buf_size);
if (ret <= 0) {
if (ret < 0)
__FILE(stream)->flags |= _IO_ERR;
else
__FILE(stream)->flags |= _IO_EOF;
break;
}
__FILE(stream)->buf_len = ret;
__FILE(stream)->buf_pos = 0;
}
LIBC_UNLOCK(__FILE(stream)->lock);
return bytes_read / size;
}
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