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// SPDX-License-Identifier: GPL-2.0-or-later
#include <stdio.h>
#include <sys/types.h>
#include <stdint.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdlib.h>
#include <unistd.h>
#include <string.h>
#include <errno.h>
#include <stdarg.h>
#include <sys/mman.h>
#include "common.h"
int read_file_2(const char *filename, size_t *size, void **outbuf, size_t max_size)
{
off_t fsize;
ssize_t rsize;
int ret, fd;
void *buf;
*size = 0;
*outbuf = NULL;
fd = open(filename, O_RDONLY);
if (fd < 0) {
fprintf(stderr, "Cannot open %s: %s\n", filename, strerror(errno));
return -errno;
}
fsize = lseek(fd, 0, SEEK_END);
if (fsize == -1) {
fprintf(stderr, "Cannot get size %s: %s\n", filename, strerror(errno));
ret = -errno;
goto close;
}
if (fsize < max_size)
max_size = fsize;
if (lseek(fd, 0, SEEK_SET) == -1) {
fprintf(stderr, "Cannot seek to start %s: %s\n", filename, strerror(errno));
ret = -errno;
goto close;
}
buf = mmap(NULL, max_size, PROT_READ | PROT_WRITE, MAP_PRIVATE, fd, 0);
if (buf == MAP_FAILED ) {
buf = malloc(max_size);
if (!buf) {
fprintf(stderr, "Cannot allocate memory\n");
ret = -ENOMEM;
goto close;
}
*outbuf = buf;
while (*size < max_size) {
rsize = read(fd, buf, max_size - *size);
if (rsize == 0) {
ret = -EIO;
goto free;
}
if (rsize < 0) {
ret = -errno;
goto free;
}
buf += rsize;
*size += rsize;
}
} else {
*outbuf = buf;
*size = max_size;
}
ret = 0;
goto close;
free:
*outbuf = NULL;
free(buf);
close:
close(fd);
return ret;
}
void *read_file(const char *filename, size_t *size)
{
int ret;
void *buf;
ret = read_file_2(filename, size, &buf, (size_t)-1);
if (!ret)
return buf;
errno = -ret;
return NULL;
}
int write_file(const char *filename, const void *buf, size_t size)
{
int fd, ret = 0;
int now;
fd = open(filename, O_WRONLY | O_TRUNC | O_CREAT,
S_IRUSR | S_IWUSR | S_IRGRP | S_IROTH);
if (fd < 0) {
fprintf(stderr, "Cannot open %s: %s\n", filename, strerror(errno));
return -errno;
}
while (size) {
now = write(fd, buf, size);
if (now < 0) {
fprintf(stderr, "Cannot write to %s: %s\n", filename,
strerror(errno));
ret = -errno;
goto out;
}
size -= now;
buf += now;
}
out:
close(fd);
return ret;
}
int read_full(int fd, void *buf, size_t size)
{
size_t insize = size;
int now;
int total = 0;
while (size) {
now = read(fd, buf, size);
if (now == 0)
return total;
if (now < 0)
return now;
total += now;
size -= now;
buf += now;
}
return insize;
}
int write_full(int fd, void *buf, size_t size)
{
size_t insize = size;
int now;
while (size) {
now = write(fd, buf, size);
if (now <= 0)
return now;
size -= now;
buf += now;
}
return insize;
}
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