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/* -*- Mode: c; tab-width: 8; c-basic-offset: 4; indent-tabs-mode: t; -*- */
/* cairo-output-stream.c: Output stream abstraction
*
* Copyright © 2005 Red Hat, Inc
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
* http://www.mozilla.org/MPL/
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
* The Original Code is the cairo graphics library.
* The Initial Developer of the Original Code is Red Hat, Inc.
* Author(s):
* Kristian Høgsberg <krh@redhat.com>
*/
#define _DEFAULT_SOURCE /* for snprintf() */
#include "cairoint.h"
#include "cairo-output-stream-private.h"
#include "cairo-array-private.h"
#include "cairo-error-private.h"
#include "cairo-compiler-private.h"
#include <stdio.h>
#include <errno.h>
/* Numbers printed with %f are printed with this number of significant
* digits after the decimal.
#define SIGNIFICANT_DIGITS_AFTER_DECIMAL 6
/* Numbers printed with %g are assumed to only have %CAIRO_FIXED_FRAC_BITS
* bits of precision available after the decimal point.
* FIXED_POINT_DECIMAL_DIGITS specifies the minimum number of decimal
* digits after the decimal point required to preserve the available
* precision.
* The conversion is:
* <programlisting>
* FIXED_POINT_DECIMAL_DIGITS = ceil( CAIRO_FIXED_FRAC_BITS * ln(2)/ln(10) )
* </programlisting>
* We can replace ceil(x) with (int)(x+1) since x will never be an
* integer for any likely value of %CAIRO_FIXED_FRAC_BITS.
#define FIXED_POINT_DECIMAL_DIGITS ((int)(CAIRO_FIXED_FRAC_BITS*0.301029996 + 1))
void
_cairo_output_stream_init (cairo_output_stream_t *stream,
cairo_output_stream_write_func_t write_func,
cairo_output_stream_flush_func_t flush_func,
cairo_output_stream_close_func_t close_func)
{
stream->write_func = write_func;
stream->flush_func = flush_func;
stream->close_func = close_func;
stream->position = 0;
stream->status = CAIRO_STATUS_SUCCESS;
stream->closed = FALSE;
}
cairo_status_t
_cairo_output_stream_fini (cairo_output_stream_t *stream)
return _cairo_output_stream_close (stream);
const cairo_output_stream_t _cairo_output_stream_nil = {
NULL, /* write_func */
NULL, /* flush_func */
NULL, /* close_func */
0, /* position */
CAIRO_STATUS_NO_MEMORY,
FALSE /* closed */
};
static const cairo_output_stream_t _cairo_output_stream_nil_write_error = {
CAIRO_STATUS_WRITE_ERROR,
typedef struct _cairo_output_stream_with_closure {
cairo_output_stream_t base;
cairo_write_func_t write_func;
cairo_close_func_t close_func;
void *closure;
} cairo_output_stream_with_closure_t;
static cairo_status_t
closure_write (cairo_output_stream_t *stream,
const unsigned char *data, unsigned int length)
cairo_output_stream_with_closure_t *stream_with_closure =
(cairo_output_stream_with_closure_t *) stream;
if (stream_with_closure->write_func == NULL)
return CAIRO_STATUS_SUCCESS;
return stream_with_closure->write_func (stream_with_closure->closure,
data, length);
closure_close (cairo_output_stream_t *stream)
if (stream_with_closure->close_func != NULL)
return stream_with_closure->close_func (stream_with_closure->closure);
else
cairo_output_stream_t *
_cairo_output_stream_create (cairo_write_func_t write_func,
cairo_close_func_t close_func,
void *closure)
cairo_output_stream_with_closure_t *stream;
stream = _cairo_calloc (sizeof (cairo_output_stream_with_closure_t));
if (unlikely (stream == NULL)) {
_cairo_error_throw (CAIRO_STATUS_NO_MEMORY);
return (cairo_output_stream_t *) &_cairo_output_stream_nil;
_cairo_output_stream_init (&stream->base,
closure_write, NULL, closure_close);
stream->closure = closure;
return &stream->base;
_cairo_output_stream_create_in_error (cairo_status_t status)
cairo_output_stream_t *stream;
/* check for the common ones */
if (status == CAIRO_STATUS_NO_MEMORY)
if (status == CAIRO_STATUS_WRITE_ERROR)
return (cairo_output_stream_t *) &_cairo_output_stream_nil_write_error;
stream = _cairo_calloc (sizeof (cairo_output_stream_t));
_cairo_output_stream_init (stream, NULL, NULL, NULL);
stream->status = status;
return stream;
_cairo_output_stream_flush (cairo_output_stream_t *stream)
cairo_status_t status;
if (stream->closed)
return stream->status;
if (stream == &_cairo_output_stream_nil ||
stream == &_cairo_output_stream_nil_write_error)
if (stream->flush_func) {
status = stream->flush_func (stream);
/* Don't overwrite a pre-existing status failure. */
if (stream->status == CAIRO_STATUS_SUCCESS)
_cairo_output_stream_close (cairo_output_stream_t *stream)
if (stream->close_func) {
status = stream->close_func (stream);
stream->closed = TRUE;
_cairo_output_stream_destroy (cairo_output_stream_t *stream)
assert (stream != NULL);
status = _cairo_output_stream_fini (stream);
free (stream);
return status;
_cairo_output_stream_write (cairo_output_stream_t *stream,
const void *data, size_t length)
if (length == 0 || stream->status)
return;
if (stream->closed) {
stream->status = CAIRO_STATUS_WRITE_ERROR;
stream->status = stream->write_func (stream, data, length);
stream->position += length;
_cairo_output_stream_write_hex_string (cairo_output_stream_t *stream,
const unsigned char *data,
size_t length)
const char hex_chars[] = "0123456789abcdef";
char buffer[2];
unsigned int i, column;
for (i = 0, column = 0; i < length; i++, column++) {
if (column == 38) {
_cairo_output_stream_write (stream, "\n", 1);
column = 0;
buffer[0] = hex_chars[(data[i] >> 4) & 0x0f];
buffer[1] = hex_chars[data[i] & 0x0f];
_cairo_output_stream_write (stream, buffer, 2);
/* Format a double in a locale independent way and trim trailing
* zeros. Based on code from Alex Larson <alexl@redhat.com>.
* https://mail.gnome.org/archives/gtk-devel-list/2001-October/msg00087.html
* The code in the patch is copyright Red Hat, Inc under the LGPL, but
* has been relicensed under the LGPL/MPL dual license for inclusion
* into cairo (see COPYING). -- Kristian Høgsberg <krh@redhat.com>
static void
_cairo_dtostr (char *buffer, size_t size, double d, cairo_bool_t limited_precision)
const char *decimal_point;
int decimal_point_len;
char *p;
int decimal_len;
int num_zeros, decimal_digits;
/* Omit the minus sign from negative zero. */
if (d == 0.0)
d = 0.0;
decimal_point = _cairo_get_locale_decimal_point ();
decimal_point_len = strlen (decimal_point);
assert (decimal_point_len != 0);
if (limited_precision) {
snprintf (buffer, size, "%.*f", FIXED_POINT_DECIMAL_DIGITS, d);
} else {
/* Using "%f" to print numbers less than 0.1 will result in
* reduced precision due to the default 6 digits after the
* decimal point.
* For numbers is < 0.1, we print with maximum precision and count
* the number of zeros between the decimal point and the first
* significant digit. We then print the number again with the
* number of decimal places that gives us the required number of
* significant digits. This ensures the number is correctly
* rounded.
if (fabs (d) >= 0.1) {
snprintf (buffer, size, "%f", d);
snprintf (buffer, size, "%.18f", d);
p = buffer;
if (*p == '+' || *p == '-')
p++;
while (_cairo_isdigit (*p))
if (strncmp (p, decimal_point, decimal_point_len) == 0)
p += decimal_point_len;
num_zeros = 0;
while (*p++ == '0')
num_zeros++;
decimal_digits = num_zeros + SIGNIFICANT_DIGITS_AFTER_DECIMAL;
if (decimal_digits < 18)
snprintf (buffer, size, "%.*f", decimal_digits, d);
if (strncmp (p, decimal_point, decimal_point_len) == 0) {
*p = '.';
decimal_len = strlen (p + decimal_point_len);
memmove (p + 1, p + decimal_point_len, decimal_len);
p[1 + decimal_len] = 0;
/* Remove trailing zeros and decimal point if possible. */
for (p = p + decimal_len; *p == '0'; p--)
*p = 0;
if (*p == '.') {
p--;
enum {
LENGTH_MODIFIER_LONG = 0x100,
LENGTH_MODIFIER_LONG_LONG = 0x200
/* Here's a limited reimplementation of printf. The reason for doing
* this is primarily to special case handling of doubles. We want
* locale independent formatting of doubles and we want to trim
* trailing zeros. This is handled by dtostr() above, and the code
* below handles everything else by calling snprintf() to do the
* formatting. This functionality is only for internal use and we
* only implement the formats we actually use.
_cairo_output_stream_vprintf (cairo_output_stream_t *stream,
const char *fmt, va_list ap)
#define SINGLE_FMT_BUFFER_SIZE 32
char buffer[512], single_fmt[SINGLE_FMT_BUFFER_SIZE];
int single_fmt_length;
const char *f, *start;
int length_modifier, width;
cairo_bool_t var_width;
f = fmt;
while (*f != '\0') {
if (p == buffer + sizeof (buffer)) {
_cairo_output_stream_write (stream, buffer, sizeof (buffer));
if (*f != '%') {
*p++ = *f++;
continue;
start = f;
f++;
if (*f == '0')
var_width = FALSE;
if (*f == '*') {
var_width = TRUE;
while (_cairo_isdigit (*f))
length_modifier = 0;
if (*f == 'l') {
length_modifier = LENGTH_MODIFIER_LONG;
length_modifier = LENGTH_MODIFIER_LONG_LONG;
/* The only format strings exist in the cairo implementation
* itself. So there's an internal consistency problem if any
* of them is larger than our format buffer size. */
single_fmt_length = f - start + 1;
assert (single_fmt_length + 1 <= SINGLE_FMT_BUFFER_SIZE);
/* Reuse the format string for this conversion. */
memcpy (single_fmt, start, single_fmt_length);
single_fmt[single_fmt_length] = '\0';
/* Flush contents of buffer before snprintf()'ing into it. */
_cairo_output_stream_write (stream, buffer, p - buffer);
/* We group signed and unsigned together in this switch, the
* only thing that matters here is the size of the arguments,
* since we're just passing the data through to sprintf(). */
switch (*f | length_modifier) {
case '%':
buffer[0] = *f;
buffer[1] = 0;
break;
case 'd':
case 'u':
case 'o':
case 'x':
case 'X':
if (var_width) {
width = va_arg (ap, int);
snprintf (buffer, sizeof buffer,
single_fmt, width, va_arg (ap, int));
snprintf (buffer, sizeof buffer, single_fmt, va_arg (ap, int));
case 'd' | LENGTH_MODIFIER_LONG:
case 'u' | LENGTH_MODIFIER_LONG:
case 'o' | LENGTH_MODIFIER_LONG:
case 'x' | LENGTH_MODIFIER_LONG:
case 'X' | LENGTH_MODIFIER_LONG:
single_fmt, width, va_arg (ap, long int));
single_fmt, va_arg (ap, long int));
case 'd' | LENGTH_MODIFIER_LONG_LONG:
case 'u' | LENGTH_MODIFIER_LONG_LONG:
case 'o' | LENGTH_MODIFIER_LONG_LONG:
case 'x' | LENGTH_MODIFIER_LONG_LONG:
case 'X' | LENGTH_MODIFIER_LONG_LONG:
single_fmt, width, va_arg (ap, long long int));
single_fmt, va_arg (ap, long long int));
case 's': {
/* Write out strings as they may be larger than the buffer. */
const char *s = va_arg (ap, const char *);
int len = strlen(s);
_cairo_output_stream_write (stream, s, len);
buffer[0] = 0;
case 'f':
_cairo_dtostr (buffer, sizeof buffer, va_arg (ap, double), FALSE);
case 'g':
_cairo_dtostr (buffer, sizeof buffer, va_arg (ap, double), TRUE);
case 'c':
buffer[0] = va_arg (ap, int);
default:
ASSERT_NOT_REACHED;
p = buffer + strlen (buffer);
_cairo_output_stream_printf (cairo_output_stream_t *stream,
const char *fmt, ...)
va_list ap;
va_start (ap, fmt);
_cairo_output_stream_vprintf (stream, fmt, ap);
va_end (ap);
/* Matrix elements that are smaller than the value of the largest element * MATRIX_ROUNDING_TOLERANCE
* are rounded down to zero. */
#define MATRIX_ROUNDING_TOLERANCE 1e-12
_cairo_output_stream_print_matrix (cairo_output_stream_t *stream,
const cairo_matrix_t *matrix)
cairo_matrix_t m;
double s, e;
m = *matrix;
s = fabs (m.xx);
if (fabs (m.xy) > s)
s = fabs (m.xy);
if (fabs (m.yx) > s)
s = fabs (m.yx);
if (fabs (m.yy) > s)
s = fabs (m.yy);
e = s * MATRIX_ROUNDING_TOLERANCE;
if (fabs(m.xx) < e)
m.xx = 0;
if (fabs(m.xy) < e)
m.xy = 0;
if (fabs(m.yx) < e)
m.yx = 0;
if (fabs(m.yy) < e)
m.yy = 0;
if (fabs(m.x0) < e)
m.x0 = 0;
if (fabs(m.y0) < e)
m.y0 = 0;
_cairo_output_stream_printf (stream,
"%f %f %f %f %f %f",
m.xx, m.yx, m.xy, m.yy, m.x0, m.y0);
long long
_cairo_output_stream_get_position (cairo_output_stream_t *stream)
return stream->position;
_cairo_output_stream_get_status (cairo_output_stream_t *stream)
/* Maybe this should be a configure time option, so embedded targets
* don't have to pull in stdio. */
typedef struct _stdio_stream {
FILE *file;
} stdio_stream_t;
stdio_write (cairo_output_stream_t *base,
stdio_stream_t *stream = (stdio_stream_t *) base;
if (fwrite (data, 1, length, stream->file) != length)
return _cairo_error (CAIRO_STATUS_WRITE_ERROR);
stdio_flush (cairo_output_stream_t *base)
fflush (stream->file);
if (ferror (stream->file))
stdio_close (cairo_output_stream_t *base)
status = stdio_flush (base);
fclose (stream->file);
_cairo_output_stream_create_for_file (FILE *file)
stdio_stream_t *stream;
if (file == NULL) {
_cairo_error_throw (CAIRO_STATUS_WRITE_ERROR);
stream = _cairo_calloc (sizeof *stream);
stdio_write, stdio_flush, stdio_flush);
stream->file = file;
_cairo_output_stream_create_for_filename (const char *filename)
if (filename == NULL)
return _cairo_null_stream_create ();
status = _cairo_fopen (filename, "wb", &file);
if (status != CAIRO_STATUS_SUCCESS)
return _cairo_output_stream_create_in_error (status);
switch (errno) {
case ENOMEM:
fclose (file);
stdio_write, stdio_flush, stdio_close);
typedef struct _memory_stream {
cairo_array_t array;
} memory_stream_t;
memory_write (cairo_output_stream_t *base,
memory_stream_t *stream = (memory_stream_t *) base;
return _cairo_array_append_multiple (&stream->array, data, length);
memory_close (cairo_output_stream_t *base)
_cairo_array_fini (&stream->array);
_cairo_memory_stream_create (void)
memory_stream_t *stream;
_cairo_output_stream_init (&stream->base, memory_write, NULL, memory_close);
_cairo_array_init (&stream->array, 1);
_cairo_memory_stream_destroy (cairo_output_stream_t *abstract_stream,
unsigned char **data_out,
unsigned long *length_out)
status = abstract_stream->status;
if (unlikely (status))
return _cairo_output_stream_destroy (abstract_stream);
stream = (memory_stream_t *) abstract_stream;
*length_out = _cairo_array_num_elements (&stream->array);
*data_out = _cairo_calloc (*length_out);
if (unlikely (*data_out == NULL)) {
status = _cairo_output_stream_destroy (abstract_stream);
assert (status == CAIRO_STATUS_SUCCESS);
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
memcpy (*data_out, _cairo_array_index (&stream->array, 0), *length_out);
_cairo_memory_stream_copy (cairo_output_stream_t *base,
cairo_output_stream_t *dest)
if (base->status) {
dest->status = base->status;
_cairo_output_stream_write (dest,
_cairo_array_index (&stream->array, 0),
_cairo_array_num_elements (&stream->array));
int
_cairo_memory_stream_length (cairo_output_stream_t *base)
return _cairo_array_num_elements (&stream->array);
null_write (cairo_output_stream_t *base,
_cairo_null_stream_create (void)
_cairo_output_stream_init (stream, null_write, NULL, NULL);