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Ignore whitespace Rev 4376 → Rev 4377

/branches/tracing/uspace/lib/libc/generic/io/stdio.c
0,0 → 1,278
/*
* Copyright (c) 2008 Jiri Svoboda
* All rights reserved.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* - Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* - Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* - The name of the author may not be used to endorse or promote products
* derived from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
 
/** @addtogroup libc
* @{
*/
/**
* @file
* @brief ANSI C Stream I/O.
*/
 
#include <stdlib.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <unistd.h>
#include <errno.h>
#include <bool.h>
#include <stdio.h>
 
FILE *stdin, *stdout, *stderr;
 
/**
* Open a stream.
*
* @param file_name Name of the file to open.
* @param mode Mode string, (r|w|a)[b|t][+].
*/
FILE *fopen(const char *file_name, const char *mode)
{
FILE *f;
int flags;
bool plus;
const char *mp;
 
/* Parse mode except first character. */
 
mp = mode;
if (*mp++ == '\0') {
errno = EINVAL;
return NULL;
}
 
if (*mp == 'b' || *mp == 't') ++mp;
 
if (*mp == '+') {
++mp;
plus = true;
} else {
plus = false;
}
 
if (*mp != '\0') {
errno = EINVAL;
return NULL;
}
 
/* Parse first character of mode and determine flags for open(). */
 
switch (mode[0]) {
case 'r':
flags = plus ? O_RDWR : O_RDONLY;
break;
case 'w':
flags = (O_TRUNC | O_CREAT) | (plus ? O_RDWR : O_WRONLY);
break;
case 'a':
/* TODO: a+ must read from beginning, append to the end. */
if (plus) {
errno = ENOTSUP;
return NULL;
}
flags = (O_APPEND | O_CREAT) | (plus ? O_RDWR : O_WRONLY);
default:
errno = EINVAL;
return NULL;
}
 
/* Open file. */
f = malloc(sizeof(FILE));
if (f == NULL) {
errno = ENOMEM;
return NULL;
}
 
f->fd = open(file_name, flags, 0666);
if (f->fd < 0) {
free(f);
return NULL; /* errno was set by open() */
}
 
f->error = 0;
f->eof = 0;
 
return f;
}
 
/** Close a stream.
*
* @param f Pointer to stream.
* @return 0 on success, EOF on error.
*/
int fclose(FILE *f)
{
int rc;
 
rc = close(f->fd);
free(f);
 
if (rc != 0)
return EOF; /* errno was set by close() */
 
return 0;
}
 
/** Read from a stream.
*
* @param buf Destination buffer.
* @param size Size of each record.
* @param nmemb Number of records to read.
* @param f Pointer to the stream.
*/
size_t fread(void *buf, size_t size, size_t nmemb, FILE *f)
{
size_t left, done, n;
 
left = size * nmemb;
done = 0;
 
while (left > 0 && !f->error && !f->eof) {
n = read(f->fd, buf + done, left);
 
if (n < 0) {
f->error = 1;
} else if (n == 0) {
f->eof = 1;
} else {
left -= n;
done += n;
}
}
 
return done / size;
}
 
 
/** Write to a stream.
*
* @param buf Source buffer.
* @param size Size of each record.
* @param nmemb Number of records to write.
* @param f Pointer to the stream.
*/
size_t fwrite(const void *buf, size_t size, size_t nmemb, FILE *f)
{
size_t left, done, n;
 
left = size * nmemb;
done = 0;
 
while (left > 0 && !f->error) {
n = write(f->fd, buf + done, left);
 
if (n <= 0) {
f->error = 1;
} else {
left -= n;
done += n;
}
}
 
return done / size;
}
 
/** Return the end-of-file indicator of a stream. */
int feof(FILE *f)
{
return f->eof;
}
 
/** Return the error indicator of a stream. */
int ferror(FILE *f)
{
return f->error;
}
 
/** Clear the error and end-of-file indicators of a stream. */
void clearerr(FILE *f)
{
f->eof = 0;
f->error = 0;
}
 
/** Read character from a stream. */
int fgetc(FILE *f)
{
unsigned char c;
size_t n;
 
n = fread(&c, sizeof(c), 1, f);
if (n < 1) return EOF;
 
return (int) c;
}
 
/** Write character to a stream. */
int fputc(int c, FILE *f)
{
unsigned char cc;
size_t n;
 
cc = (unsigned char) c;
n = fwrite(&cc, sizeof(cc), 1, f);
if (n < 1) return EOF;
 
return (int) cc;
}
 
/** Write string to a stream. */
int fputs(const char *s, FILE *f)
{
int rc;
 
rc = 0;
 
while (*s && rc >= 0) {
rc = fputc(*s++, f);
}
 
if (rc < 0) return EOF;
 
return 0;
}
 
/** Seek to position in stream. */
int fseek(FILE *f, long offset, int origin)
{
off_t rc;
 
rc = lseek(f->fd, offset, origin);
if (rc == (off_t) (-1)) {
/* errno has been set by lseek. */
return -1;
}
 
f->eof = 0;
 
return 0;
}
 
/** @}
*/