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/*C
(c) 2005 bl0rg.net
**/
#include "conf.h"
#include <assert.h>
#include <stdio.h>
#include <errno.h>
#include <sys/types.h>
#include <sys/uio.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#include <sys/stat.h>
#include "file.h"
#include "misc.h"
/*M
\emph{Read and retry on interrupted system calls.}
**/
int file_read(file_t *file, unsigned char *buf, size_t size) {
assert(file != NULL);
assert(buf != NULL);
assert(size > 0);
return unix_read(file->fd, buf, size);
}
/*M
\emph{Seek forward in the file.}
**/
int file_seek_fwd(file_t *file, size_t size) {
if (lseek(file->fd, size, SEEK_CUR) < 0)
return 0;
else
return 1;
}
/*M
\emph{Open a file.}
Return 0 on error, 1 on success. To read from STDIN, call with "-"
as filename.
**/
int file_open_read(file_t *file, char *filename) {
assert(file != NULL);
assert(filename != NULL);
if (strcmp(filename, "-") == 0) {
/* read from stdin */
file->fd = STDIN_FILENO;
file->size = 0;
} else {
file->fd = open(filename, O_RDONLY);
if (file->fd < 0) {
perror("open");
return 0;
}
struct stat sb;
if (stat(filename, &sb) < 0) {
perror("stat");
return 0;
}
file->size = (unsigned long)sb.st_size;
}
file->offset = 0;
return 1;
}
/*M
\emph{Write a buffer to filedescriptor fd.}
**/
int file_write(file_t *file, unsigned char *buf, size_t size) {
assert(file != NULL);
assert(buf != NULL);
return unix_write(file->fd, buf, size);
}
/*M
\emph{Open a file for writing.}
**/
int file_open_write(file_t *file, char *filename) {
assert(file != NULL);
assert(filename != NULL);
if (!strcmp(filename, "-"))
/* write to stdout */
file->fd = STDOUT_FILENO;
else {
file->fd = open(filename, O_WRONLY | O_CREAT | O_TRUNC,
S_IRWXU | S_IRGRP | S_IROTH);
if (file->fd < 0) {
perror("open");
return 0;
}
}
file->offset = 0;
return 1;
}
/*M
\emph{Close a file.}
Return 0 on error and 1 on success.
**/
int file_close(file_t *file) {
assert(file != NULL);
if (file->fd != STDIN_FILENO) {
if (close(file->fd) < 0) {
perror("close");
return 0;
}
}
return 1;
}
/*C
**/
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