/**
* \file output.c
* \brief Generic stdio-like output interface
* \author Abramo Bagnara <abramo@alsa-project.org>
* \date 2000
*
* Generic stdio-like output interface
*/
/*
* Output object
* Copyright (c) 2000 by Abramo Bagnara <abramo@alsa-project.org>
*
*
* This library is free software; you can redistribute it and/or modify
* it under the terms of the GNU Lesser General Public License as
* published by the Free Software Foundation; either version 2.1 of
* the License, or (at your option) any later version.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
* GNU Lesser General Public License for more details.
*
* You should have received a copy of the GNU Lesser General Public
* License along with this library; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA
*
*/
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include "local.h"
#ifndef DOC_HIDDEN
typedef struct _snd_output_ops {
int (*close)(snd_output_t *output);
int (*print)(snd_output_t *output, const char *format, va_list args);
int (*puts)(snd_output_t *output, const char *str);
int (*putch)(snd_output_t *output, int c);
int (*flush)(snd_output_t *output);
} snd_output_ops_t;
struct _snd_output {
snd_output_type_t type;
const snd_output_ops_t *ops;
void *private_data;
};
#endif
/**
* \brief Closes an output handle.
* \param output The output handle to be closed.
* \return Zero if successful, otherwise a negative error code.
*/
int snd_output_close(snd_output_t *output)
{
int err = output->ops->close(output);
free(output);
return err;
}
/**
* \brief Writes formatted output (like \c fprintf(3)) to an output handle.
* \param output The output handle.
* \param format Format string in \c fprintf format.
* \param ... Other \c fprintf arguments.
* \return The number of characters written, or a negative error code.
*/
int snd_output_printf(snd_output_t *output, const char *format, ...)
{
int result;
va_list args;
va_start(args, format);
result = output->ops->print(output, format, args);
va_end(args);
return result;
}
/**
* \brief Writes formatted output (like \c fprintf(3)) to an output handle.
* \param output The output handle.
* \param format Format string in \c fprintf format.
* \param args Other \c fprintf arguments.
* \return The number of characters written, or a negative error code.
*/
int snd_output_vprintf(snd_output_t *output, const char *format, va_list args)
{
return output->ops->print(output, format, args);
}
/**
* \brief Writes a string to an output handle (like \c fputs(3)).
* \param output The output handle.
* \param str Pointer to the string.
* \return Zero if successful, otherwise a negative error code or \c EOF.
*/
int snd_output_puts(snd_output_t *output, const char *str)
{
return output->ops->puts(output, str);
}
/**
* \brief Writes a character to an output handle (like \c putc(3)).
* \param output The output handle.
* \param c The character.
* \return Zero if successful, otherwise a negative error code or \c EOF.
*/
int snd_output_putc(snd_output_t *output, int c)
{
return output->ops->putch(output, c);
}
/**
* \brief Flushes an output handle (like fflush(3)).
* \param output The output handle.
* \return Zero if successful, otherwise \c EOF.
*
* If the underlying destination is a stdio stream, this function calls
* \c fflush. If the underlying destination is a memory buffer, the write
* position is reset to the beginning of the buffer. \c =:-o
*/
int snd_output_flush(snd_output_t *output)
{
return output->ops->flush(output);
}
#ifndef DOC_HIDDEN
typedef struct _snd_output_stdio {
int close;
FILE *fp;
} snd_output_stdio_t;
static int snd_output_stdio_close(snd_output_t *output)
{
snd_output_stdio_t *stdio = output->private_data;
if (stdio->close)
fclose(stdio->fp);
free(stdio);
return 0;
}
static int snd_output_stdio_print(snd_output_t *output, const char *format, va_list args)
{
snd_output_stdio_t *stdio = output->private_data;
return vfprintf(stdio->fp, format, args);
}
static int snd_output_stdio_puts(snd_output_t *output, const char *str)
{
snd_output_stdio_t *stdio = output->private_data;
return fputs(str, stdio->fp);
}
static int snd_output_stdio_putc(snd_output_t *output, int c)
{
snd_output_stdio_t *stdio = output->private_data;
return putc(c, stdio->fp);
}
static int snd_output_stdio_flush(snd_output_t *output)
{
snd_output_stdio_t *stdio = output->private_data;
return fflush(stdio->fp);
}
static const snd_output_ops_t snd_output_stdio_ops = {
.close = snd_output_stdio_close,
.print = snd_output_stdio_print,
.puts = snd_output_stdio_puts,
.putch = snd_output_stdio_putc,
.flush = snd_output_stdio_flush,
};
#endif
/**
* \brief Creates a new output object using an existing stdio \c FILE pointer.
* \param outputp The function puts the pointer to the new output object
* at the address specified by \p outputp.
* \param fp The \c FILE pointer to write to. Characters are written
* to the file starting at the current file position.
* \param _close Close flag. Set this to 1 if #snd_output_close should close
* \p fp by calling \c fclose.
* \return Zero if successful, otherwise a negative error code.
*/
int snd_output_stdio_attach(snd_output_t **outputp, FILE *fp, int _close)
{
snd_output_t *output;
snd_output_stdio_t *stdio;
assert(outputp && fp);
stdio = calloc(1, sizeof(*stdio));
if (!stdio)
return -ENOMEM;
output = calloc(1, sizeof(*output));
if (!output) {
free(stdio);
return -ENOMEM;
}
stdio->fp = fp;
stdio->close = _close;
output->type = SND_OUTPUT_STDIO;
output->ops = &snd_output_stdio_ops;
output->private_data = stdio;
*outputp = output;
return 0;
}
/**
* \brief Creates a new output object writing to a file.
* \param outputp The function puts the pointer to the new output object
* at the address specified by \p outputp.
* \param file The name of the file to open.
* \param mode The open mode, like \c fopen(3).
* \return Zero if successful, otherwise a negative error code.
*/
int snd_output_stdio_open(snd_output_t **outputp, const char *file, const char *mode)
{
int err;
FILE *fp = fopen(file, mode);
if (!fp) {
//SYSERR("fopen");
return -errno;
}
err = snd_output_stdio_attach(outputp, fp, 1);
if (err < 0)
fclose(fp);
return err;
}
#ifndef DOC_HIDDEN
typedef struct _snd_output_buffer {
unsigned char *buf;
size_t alloc;
size_t size;
} snd_output_buffer_t;
static int snd_output_buffer_close(snd_output_t *output)
{
snd_output_buffer_t *buffer = output->private_data;
free(buffer->buf);
free(buffer);
return 0;
}
static int snd_output_buffer_need(snd_output_t *output, size_t size)
{
snd_output_buffer_t *buffer = output->private_data;
size_t _free = buffer->alloc - buffer->size;
size_t alloc;
unsigned char *buf;
if (_free >= size)
return _free;
if (buffer->alloc == 0)
alloc = 256;
else
alloc = buffer->alloc;
while (alloc < buffer->size + size)
alloc *= 2;
buf = realloc(buffer->buf, alloc);
if (!buf)
return -ENOMEM;
buffer->buf = buf;
buffer->alloc = alloc;
return buffer->alloc - buffer->size;
}
static int snd_output_buffer_print(snd_output_t *output, const char *format, va_list args)
{
snd_output_buffer_t *buffer = output->private_data;
size_t size = 256;
int result;
result = snd_output_buffer_need(output, size);
if (result < 0)
return result;
result = vsnprintf((char *)buffer->buf + buffer->size, size, format, args);
assert(result >= 0);
if ((size_t)result <= size) {
buffer->size += result;
return result;
}
size = result;
result = snd_output_buffer_need(output, size);
if (result < 0)
return result;
result = vsnprintf((char *)buffer->buf + buffer->size, result, format, args);
assert(result == (int)size);
buffer->size += result;
return result;
}
static int snd_output_buffer_puts(snd_output_t *output, const char *str)
{
snd_output_buffer_t *buffer = output->private_data;
size_t size = strlen(str);
int err;
err = snd_output_buffer_need(output, size);
if (err < 0)
return err;
memcpy(buffer->buf + buffer->size, str, size);
buffer->size += size;
return size;
}
static int snd_output_buffer_putc(snd_output_t *output, int c)
{
snd_output_buffer_t *buffer = output->private_data;
int err;
err = snd_output_buffer_need(output, 1);
if (err < 0)
return err;
buffer->buf[buffer->size++] = c;
return 0;
}
static int snd_output_buffer_flush(snd_output_t *output ATTRIBUTE_UNUSED)
{
snd_output_buffer_t *buffer = output->private_data;
buffer->size = 0;
return 0;
}
static const snd_output_ops_t snd_output_buffer_ops = {
.close = snd_output_buffer_close,
.print = snd_output_buffer_print,
.puts = snd_output_buffer_puts,
.putch = snd_output_buffer_putc,
.flush = snd_output_buffer_flush,
};
#endif
/**
* \brief Returns the address of the buffer of a #SND_OUTPUT_BUFFER output handle.
* \param output The output handle.
* \param buf The functions puts the current address of the buffer at the
* address specified by \p buf.
* \return The current size of valid data in the buffer.
*
* The address of the buffer may become invalid when output functions or
* #snd_output_close are called.
*/
size_t snd_output_buffer_string(snd_output_t *output, char **buf)
{
snd_output_buffer_t *buffer = output->private_data;
*buf = (char *)buffer->buf;
return buffer->size;
}
/**
* \brief Creates a new output object with an auto-extending memory buffer.
* \param outputp The function puts the pointer to the new output object
* at the address specified by \p outputp.
* \return Zero if successful, otherwise a negative error code.
*/
int snd_output_buffer_open(snd_output_t **outputp)
{
snd_output_t *output;
snd_output_buffer_t *buffer;
assert(outputp);
buffer = calloc(1, sizeof(*buffer));
if (!buffer)
return -ENOMEM;
output = calloc(1, sizeof(*output));
if (!output) {
free(buffer);
return -ENOMEM;
}
buffer->buf = NULL;
buffer->alloc = 0;
buffer->size = 0;
output->type = SND_OUTPUT_BUFFER;
output->ops = &snd_output_buffer_ops;
output->private_data = buffer;
*outputp = output;
return 0;
}