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/* -*- Mode: c; c-basic-offset: 4; indent-tabs-mode: t; tab-width: 8; -*- */
/* cairo - a vector graphics library with display and print output
*
* Copyright © 2016 Adrian Johnson
*
* 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
*
* 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 Adrian Johnson.
*
* Contributor(s):
* Adrian Johnson <ajohnson@redneon.com>
*/
#include "cairoint.h"
#include "cairo-array-private.h"
#include "cairo-list-inline.h"
#include "cairo-tag-attributes-private.h"
#include "cairo-tag-stack-private.h"
#include <string.h>
typedef enum {
ATTRIBUTE_BOOL, /* Either true/false or 1/0 may be used. */
ATTRIBUTE_INT,
ATTRIBUTE_FLOAT, /* Decimal separator is in current locale. */
ATTRIBUTE_STRING, /* Enclose in single quotes. String escapes:
* \' - single quote
* \\ - backslash
*/
} attribute_type_t;
typedef struct _attribute_spec {
const char *name;
attribute_type_t type;
int array_size; /* 0 = scalar, -1 = variable size array */
} attribute_spec_t;
/*
* name [required] Unique name of this destination (UTF-8)
* x [optional] x coordinate of destination on page. Default is x coord of
* extents of operations enclosed by the dest begin/end tags.
* y [optional] y coordinate of destination on page. Default is y coord of
* extents of operations enclosed by the dest begin/end tags.
* internal [optional] If true, the name may be optimized out of the PDF where
* possible. Default false.
*/
static attribute_spec_t _dest_attrib_spec[] = {
{ "name", ATTRIBUTE_STRING },
{ "x", ATTRIBUTE_FLOAT },
{ "y", ATTRIBUTE_FLOAT },
{ "internal", ATTRIBUTE_BOOL },
{ NULL }
};
/*
* rect [optional] One or more rectangles to define link region. Default
* is the extents of the operations enclosed by the link begin/end tags.
* Each rectangle is specified by four array elements: x, y, width, height.
* ie the array size must be a multiple of four.
*
* Internal Links
* --------------
* either:
* dest - name of dest tag in the PDF file to link to (UTF8)
* or
* page - Page number in the PDF file to link to
* pos - [optional] Position of destination on page. Default is 0,0.
*
* URI Links
* ---------
* uri [required] Uniform resource identifier (ASCII).
* File Links
* ----------
* file - [required] File name of PDF file to link to.
* either:
* dest - name of dest tag in the PDF file to link to (UTF8)
* or
* page - Page number in the PDF file to link to
* pos - [optional] Position of destination on page. Default is 0,0.
*/
static attribute_spec_t _link_attrib_spec[] =
{
{ "rect", ATTRIBUTE_FLOAT, -1 },
{ "dest", ATTRIBUTE_STRING },
{ "uri", ATTRIBUTE_STRING },
{ "file", ATTRIBUTE_STRING },
{ "page", ATTRIBUTE_INT },
{ "pos", ATTRIBUTE_FLOAT, 2 },
{ NULL }
};
/*
* Required:
* Columns - width of the image in pixels.
* Rows - height of the image in scan lines.
*
* Optional:
* K - An integer identifying the encoding scheme used. < 0 is 2 dimensional
* Group 4, = 0 is Group3 1 dimensional, > 0 is mixed 1 and 2 dimensional
* encoding. Default: 0.
* EndOfLine - If true end-of-line bit patterns are present. Default: false.
* EncodedByteAlign - If true the end of line is padded with 0 bits so the next
* line begins on a byte boundary. Default: false.
* EndOfBlock - If true the data contains an end-of-block pattern. Default: true.
* BlackIs1 - If true 1 bits are black pixels. Default: false.
* DamagedRowsBeforeError - Number of damages rows tolerated before an error
* occurs. Default: 0.
*/
static attribute_spec_t _ccitt_params_spec[] =
{
{ "Columns", ATTRIBUTE_INT },
{ "Rows", ATTRIBUTE_INT },
{ "K", ATTRIBUTE_INT },
{ "EndOfLine", ATTRIBUTE_BOOL },
{ "EncodedByteAlign", ATTRIBUTE_BOOL },
{ "EndOfBlock", ATTRIBUTE_BOOL },
{ "BlackIs1", ATTRIBUTE_BOOL },
{ "DamagedRowsBeforeError", ATTRIBUTE_INT },
{ NULL }
};
/*
* bbox - Bounding box of EPS file. The format is [ llx lly urx ury ]
* llx - lower left x xoordinate
* lly - lower left y xoordinate
* urx - upper right x xoordinate
* ury - upper right y xoordinate
* all coordinates are in PostScript coordinates.
*/
static attribute_spec_t _eps_params_spec[] =
{
{ "bbox", ATTRIBUTE_FLOAT, 4 },
{ NULL }
};
typedef union {
cairo_bool_t b;
int i;
double f;
char *s;
} attrib_val_t;
typedef struct _attribute {
char *name;
attribute_type_t type;
int array_len; /* 0 = scalar */
attrib_val_t scalar;
cairo_array_t array; /* array of attrib_val_t */
cairo_list_t link;
} attribute_t;
static const char *
skip_space (const char *p)
{
while (_cairo_isspace (*p))
p++;
return p;
}
static const char *
parse_bool (const char *p, cairo_bool_t *b)
{
if (*p == '1') {
*b = TRUE;
return p + 1;
} else if (*p == '0') {
*b = FALSE;
return p + 1;
} else if (strcmp (p, "true") == 0) {
*b = TRUE;
return p + 4;
} else if (strcmp (p, "false") == 0) {
*b = FALSE;
return p + 5;
}
return NULL;
}
static const char *
parse_int (const char *p, int *i)
{
int n;
if (sscanf(p, "%d%n", i, &n) > 0)
return p + n;
return NULL;
}
static const char *
parse_float (const char *p, double *d)
{
int n;
const char *start = p;
cairo_bool_t has_decimal_point = FALSE;
while (*p) {
if (*p == '.' || *p == ']' || _cairo_isspace (*p))
break;
p++;
}
if (*p == '.')
has_decimal_point = TRUE;
if (has_decimal_point) {
char *end;
*d = _cairo_strtod (start, &end);
if (end && end != start)
return end;
} else {
if (sscanf(start, "%lf%n", d, &n) > 0)
return start + n;
}
return NULL;
}
static const char *
decode_string (const char *p, int *len, char *s)
{
if (*p != '\'')
return NULL;
p++;
if (! *p)
return NULL;
*len = 0;
while (*p) {
if (*p == '\\') {
p++;
if (*p) {
if (s)
*s++ = *p;
p++;
(*len)++;
}
} else if (*p == '\'') {
return p + 1;
} else {
if (s)
*s++ = *p;
p++;
(*len)++;
}
}
return NULL;
}
static const char *
parse_string (const char *p, char **s)
{
const char *end;
int len;
end = decode_string (p, &len, NULL);
if (!end)
return NULL;
*s = _cairo_malloc (len + 1);
decode_string (p, &len, *s);
(*s)[len] = 0;
return end;
}
static const char *
parse_scalar (const char *p, attribute_type_t type, attrib_val_t *scalar)
{
switch (type) {
case ATTRIBUTE_BOOL:
return parse_bool (p, &scalar->b);
case ATTRIBUTE_INT:
return parse_int (p, &scalar->i);
case ATTRIBUTE_FLOAT:
return parse_float (p, &scalar->f);
case ATTRIBUTE_STRING:
return parse_string (p, &scalar->s);
}
return NULL;
}
static cairo_int_status_t
parse_array (const char *attributes, const char *p, attribute_type_t type, cairo_array_t *array, const char **end)
{
attrib_val_t val;
cairo_int_status_t status;
p = skip_space (p);
if (! *p)
goto error;
if (*p++ != '[')
goto error;
while (TRUE) {
p = skip_space (p);
if (! *p)
goto error;
if (*p == ']') {
*end = p + 1;
return CAIRO_INT_STATUS_SUCCESS;
}
p = parse_scalar (p, type, &val);
if (!p)
goto error;
status = _cairo_array_append (array, &val);
if (unlikely (status))
return status;
}
error:
return _cairo_tag_error (
"while parsing attributes: \"%s\". Error parsing array", attributes);
}
static cairo_int_status_t
parse_name (const char *attributes, const char *p, const char **end, char **s)
{
const char *p2;
char *name;
int len;
if (! _cairo_isalpha (*p))
return _cairo_tag_error (
"while parsing attributes: \"%s\". Error parsing name."
" \"%s\" does not start with an alphabetic character",
attributes, p);
p2 = p;
while (_cairo_isalpha (*p2) || _cairo_isdigit (*p2))
p2++;
len = p2 - p;
name = _cairo_malloc (len + 1);
if (unlikely (name == NULL))
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
memcpy (name, p, len);
name[len] = 0;
*s = name;
*end = p2;
return CAIRO_INT_STATUS_SUCCESS;
}
static cairo_int_status_t
parse_attributes (const char *attributes, attribute_spec_t *attrib_def, cairo_list_t *list)
{
attribute_spec_t *def;
attribute_t *attrib;
char *name = NULL;
cairo_int_status_t status;
const char *p = attributes;
if (! p)
return CAIRO_INT_STATUS_SUCCESS;
while (*p) {
p = skip_space (p);
if (! *p)
break;
status = parse_name (attributes, p, &p, &name);
if (status)
return status;
def = attrib_def;
while (def->name) {
if (strcmp (name, def->name) == 0)
break;
def++;
}
if (! def->name) {
status = _cairo_tag_error (
"while parsing attributes: \"%s\". Unknown attribute name \"%s\"",
attributes, name);
goto fail1;
}
attrib = calloc (1, sizeof (attribute_t));
if (unlikely (attrib == NULL)) {
status = _cairo_error (CAIRO_STATUS_NO_MEMORY);
goto fail1;
}
attrib->name = name;
attrib->type = def->type;
_cairo_array_init (&attrib->array, sizeof(attrib_val_t));
p = skip_space (p);
if (def->type == ATTRIBUTE_BOOL && *p != '=') {
attrib->scalar.b = TRUE;
} else {
if (*p++ != '=') {
status = _cairo_tag_error (
"while parsing attributes: \"%s\". Expected '=' after \"%s\"",
attributes, name);
goto fail2;
}
if (def->array_size == 0) {
const char *s = p;
p = parse_scalar (p, def->type, &attrib->scalar);
if (!p) {
status = _cairo_tag_error (
"while parsing attributes: \"%s\". Error parsing \"%s\"",
attributes, s);
goto fail2;
}
attrib->array_len = 0;
} else {
status = parse_array (attributes, p, def->type, &attrib->array, &p);
if (unlikely (status))
goto fail2;
attrib->array_len = _cairo_array_num_elements (&attrib->array);
if (def->array_size > 0 && attrib->array_len != def->array_size) {
status = _cairo_tag_error (
"while parsing attributes: \"%s\". Expected %d elements in array. Found %d",
attributes, def->array_size, attrib->array_len);
goto fail2;
}
}
}
cairo_list_add_tail (&attrib->link, list);
}
return CAIRO_INT_STATUS_SUCCESS;
fail2:
_cairo_array_fini (&attrib->array);
if (attrib->type == ATTRIBUTE_STRING)
free (attrib->scalar.s);
free (attrib);
fail1:
free (name);
return status;
}
static void
free_attributes_list (cairo_list_t *list)
{
attribute_t *attr, *next;
cairo_list_foreach_entry_safe (attr, next, attribute_t, list, link)
{
cairo_list_del (&attr->link);
free (attr->name);
_cairo_array_fini (&attr->array);
if (attr->type == ATTRIBUTE_STRING)
free (attr->scalar.s);
free (attr);
}
}
cairo_int_status_t
_cairo_tag_parse_link_attributes (const char *attributes, cairo_link_attrs_t *link_attrs)
{
cairo_list_t list;
cairo_int_status_t status;
attribute_t *attr;
attrib_val_t val;
cairo_bool_t has_rect = FALSE;
cairo_bool_t invalid_combination = FALSE;
cairo_list_init (&list);
status = parse_attributes (attributes, _link_attrib_spec, &list);
if (unlikely (status))
return status;
memset (link_attrs, 0, sizeof (cairo_link_attrs_t));
_cairo_array_init (&link_attrs->rects, sizeof (cairo_rectangle_t));
cairo_list_foreach_entry (attr, attribute_t, &list, link) {
if (strcmp (attr->name, "dest") == 0) {
link_attrs->dest = strdup (attr->scalar.s);
} else if (strcmp (attr->name, "page") == 0) {
link_attrs->page = attr->scalar.i;
if (link_attrs->page < 1) {
status = _cairo_tag_error ("Link attributes: \"%s\" page must be >= 1", attributes);
goto cleanup;
}
} else if (strcmp (attr->name, "pos") == 0) {
_cairo_array_copy_element (&attr->array, 0, &val);
link_attrs->pos.x = val.f;
_cairo_array_copy_element (&attr->array, 1, &val);
link_attrs->pos.y = val.f;
link_attrs->has_pos = TRUE;
} else if (strcmp (attr->name, "uri") == 0) {
link_attrs->uri = strdup (attr->scalar.s);
} else if (strcmp (attr->name, "file") == 0) {
link_attrs->file = strdup (attr->scalar.s);
} else if (strcmp (attr->name, "rect") == 0) {
cairo_rectangle_t rect;
int i;
int num_elem = _cairo_array_num_elements (&attr->array);
if (num_elem == 0 || num_elem % 4 != 0) {
status = _cairo_tag_error ("Link attributes: \"%s\" rect array size must be multiple of 4",
attributes);
goto cleanup;
}
for (i = 0; i < num_elem; i += 4) {
_cairo_array_copy_element (&attr->array, i, &val);
rect.x = val.f;
_cairo_array_copy_element (&attr->array, i+1, &val);
rect.y = val.f;
_cairo_array_copy_element (&attr->array, i+2, &val);
rect.width = val.f;
_cairo_array_copy_element (&attr->array, i+3, &val);
rect.height = val.f;
status = _cairo_array_append (&link_attrs->rects, &rect);
if (unlikely (status))
goto cleanup;
}
has_rect = TRUE;
}
}
if (link_attrs->uri) {
link_attrs->link_type = TAG_LINK_URI;
if (link_attrs->dest || link_attrs->page || link_attrs->has_pos || link_attrs->file)
invalid_combination = TRUE;
} else if (link_attrs->file) {
link_attrs->link_type = TAG_LINK_FILE;
if (link_attrs->uri)
invalid_combination = TRUE;
else if (link_attrs->dest && (link_attrs->page || link_attrs->has_pos))
invalid_combination = TRUE;
} else if (link_attrs->dest) {
link_attrs->link_type = TAG_LINK_DEST;
if (link_attrs->uri || link_attrs->page || link_attrs->has_pos)
invalid_combination = TRUE;
} else if (link_attrs->page) {
link_attrs->link_type = TAG_LINK_DEST;
if (link_attrs->uri || link_attrs->dest)
invalid_combination = TRUE;
} else {
link_attrs->link_type = TAG_LINK_EMPTY;
if (link_attrs->has_pos)
invalid_combination = TRUE;
}
if (invalid_combination) {
status = _cairo_tag_error (
"Link attributes: \"%s\" invalid combination of attributes", attributes);
}
cleanup:
free_attributes_list (&list);
if (unlikely (status)) {
free (link_attrs->dest);
free (link_attrs->uri);
free (link_attrs->file);
_cairo_array_fini (&link_attrs->rects);
}
return status;
}
cairo_int_status_t
_cairo_tag_parse_dest_attributes (const char *attributes, cairo_dest_attrs_t *dest_attrs)
{
cairo_list_t list;
cairo_int_status_t status;
attribute_t *attr;
memset (dest_attrs, 0, sizeof (cairo_dest_attrs_t));
cairo_list_init (&list);
status = parse_attributes (attributes, _dest_attrib_spec, &list);
if (unlikely (status))
goto cleanup;
cairo_list_foreach_entry (attr, attribute_t, &list, link)
{
if (strcmp (attr->name, "name") == 0) {
dest_attrs->name = strdup (attr->scalar.s);
} else if (strcmp (attr->name, "x") == 0) {
dest_attrs->x = attr->scalar.f;
dest_attrs->x_valid = TRUE;
} else if (strcmp (attr->name, "y") == 0) {
dest_attrs->y = attr->scalar.f;
dest_attrs->y_valid = TRUE;
} else if (strcmp (attr->name, "internal") == 0) {
dest_attrs->internal = attr->scalar.b;
}
}
if (! dest_attrs->name)
status = _cairo_tag_error ("Destination attributes: \"%s\" missing name attribute",
attributes);
cleanup:
free_attributes_list (&list);
return status;
}
cairo_int_status_t
_cairo_tag_parse_ccitt_params (const char *attributes, cairo_ccitt_params_t *ccitt_params)
{
cairo_list_t list;
cairo_int_status_t status;
attribute_t *attr;
ccitt_params->columns = -1;
ccitt_params->rows = -1;
/* set defaults */
ccitt_params->k = 0;
ccitt_params->end_of_line = FALSE;
ccitt_params->encoded_byte_align = FALSE;
ccitt_params->end_of_block = TRUE;
ccitt_params->black_is_1 = FALSE;
ccitt_params->damaged_rows_before_error = 0;
cairo_list_init (&list);
status = parse_attributes (attributes, _ccitt_params_spec, &list);
if (unlikely (status))
goto cleanup;
cairo_list_foreach_entry (attr, attribute_t, &list, link)
{
if (strcmp (attr->name, "Columns") == 0) {
ccitt_params->columns = attr->scalar.i;
} else if (strcmp (attr->name, "Rows") == 0) {
ccitt_params->rows = attr->scalar.i;
} else if (strcmp (attr->name, "K") == 0) {
ccitt_params->k = attr->scalar.i;
} else if (strcmp (attr->name, "EndOfLine") == 0) {
ccitt_params->end_of_line = attr->scalar.b;
} else if (strcmp (attr->name, "EncodedByteAlign") == 0) {
ccitt_params->encoded_byte_align = attr->scalar.b;
} else if (strcmp (attr->name, "EndOfBlock") == 0) {
ccitt_params->end_of_block = attr->scalar.b;
} else if (strcmp (attr->name, "BlackIs1") == 0) {
ccitt_params->black_is_1 = attr->scalar.b;
} else if (strcmp (attr->name, "DamagedRowsBeforeError") == 0) {
ccitt_params->damaged_rows_before_error = attr->scalar.b;
}
}
cleanup:
free_attributes_list (&list);
return status;
}
cairo_int_status_t
_cairo_tag_parse_eps_params (const char *attributes, cairo_eps_params_t *eps_params)
{
cairo_list_t list;
cairo_int_status_t status;
attribute_t *attr;
attrib_val_t val;
cairo_list_init (&list);
status = parse_attributes (attributes, _eps_params_spec, &list);
if (unlikely (status))
goto cleanup;
cairo_list_foreach_entry (attr, attribute_t, &list, link)
{
if (strcmp (attr->name, "bbox") == 0) {
_cairo_array_copy_element (&attr->array, 0, &val);
eps_params->bbox.p1.x = val.f;
_cairo_array_copy_element (&attr->array, 1, &val);
eps_params->bbox.p1.y = val.f;
_cairo_array_copy_element (&attr->array, 2, &val);
eps_params->bbox.p2.x = val.f;
_cairo_array_copy_element (&attr->array, 3, &val);
eps_params->bbox.p2.y = val.f;
}
}
cleanup:
free_attributes_list (&list);
return status;
}