RetroArch/compat/rxml/rxml.c
2013-01-07 02:10:54 +01:00

443 lines
9.9 KiB
C

/* RetroArch - A frontend for libretro.
* Copyright (C) 2010-2013 - Hans-Kristian Arntzen
*
* RetroArch is free software: you can redistribute it and/or modify it under the terms
* of the GNU General Public License as published by the Free Software Found-
* ation, either version 3 of the License, or (at your option) any later version.
*
* RetroArch 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 General Public License for more details.
*
* You should have received a copy of the GNU General Public License along with RetroArch.
* If not, see <http://www.gnu.org/licenses/>.
*/
#include "rxml.h"
#include <string.h>
#include <stdio.h>
#include <stddef.h>
#include <stdlib.h>
#include <ctype.h>
#include <stdint.h>
#include "../../boolean.h"
#include "../posix_string.h"
#ifndef RXML_TEST
#include "../../general.h"
#endif
struct rxml_document
{
struct rxml_node *root_node;
};
struct rxml_node *rxml_root_node(rxml_document_t *doc)
{
return doc->root_node;
}
static void rxml_free_node(struct rxml_node *node)
{
for (struct rxml_node *head = node->children; head; )
{
struct rxml_node *next_node = head->next;
rxml_free_node(head);
head = next_node;
}
for (struct rxml_attrib_node *head = node->attrib; head; )
{
struct rxml_attrib_node *next_attrib = head->next;
free(head->attrib);
free(head->value);
free(head);
head = next_attrib;
}
free(node->name);
free(node->data);
free(node);
}
static bool validate_header(const char **ptr)
{
if (memcmp(*ptr, "<?xml", 5) == 0)
{
const char *eol = strstr(*ptr, "?>\n");
if (!eol)
return false;
// Always use UTF-8. Don't really care to check.
*ptr = eol + 3;
return true;
}
else
return true;
}
static bool range_is_space(const char *begin, const char *end)
{
for (; begin < end; begin++)
if (!isspace(*begin))
return false;
return true;
}
static void skip_spaces(const char **ptr_)
{
const char *ptr = *ptr_;
while (isspace(*ptr))
ptr++;
*ptr_ = ptr;
}
static char *strdup_range(const char *begin, const char *end)
{
ptrdiff_t len = end - begin;
char *ret = (char*)malloc(len + 1);
if (!ret)
return NULL;
memcpy(ret, begin, len);
ret[len] = '\0';
return ret;
}
static char *strdup_range_escape(const char *begin, const char *end)
{
return strdup_range(begin, end); // Escaping is ignored. Assume we don't deal with that.
}
static struct rxml_attrib_node *rxml_parse_attrs(const char *str)
{
char *copy = strdup(str);
if (!copy)
return NULL;
char *last_char = copy + strlen(copy) - 1;
if (*last_char == '/')
*last_char = '\0';
struct rxml_attrib_node *list = NULL;
struct rxml_attrib_node *tail = NULL;
char *save;
const char *elem = strtok_r(copy, " \n\t\f\v\r", &save);
while (elem)
{
const char *eq = strstr(elem, "=\"");
if (!eq)
goto end;
const char *end = strrchr(eq + 2, '\"');
if (!end || end != (elem + strlen(elem) - 1))
goto end;
char *attrib = strdup_range_escape(elem, eq);
char *value = strdup_range_escape(eq + 2, end);
if (!attrib || !value)
goto end;
struct rxml_attrib_node *new_node = (struct rxml_attrib_node*)calloc(1, sizeof(*new_node));
if (!new_node)
goto end;
new_node->attrib = attrib;
new_node->value = value;
if (tail)
{
tail->next = new_node;
tail = new_node;
}
else
list = tail = new_node;
elem = strtok_r(NULL, " \n\t\f\v\r", &save);
}
end:
free(copy);
return list;
}
static char *find_first_space(const char *str)
{
while (*str && !isspace(*str))
str++;
return isspace(*str) ? (char*)str : NULL;
}
static bool rxml_parse_tag(struct rxml_node *node, const char *str)
{
const char *str_ptr = str;
skip_spaces(&str_ptr);
const char *name_end = find_first_space(str_ptr);
if (name_end)
{
node->name = strdup_range(str_ptr, name_end);
if (!node->name || !*node->name)
return false;
node->attrib = rxml_parse_attrs(name_end);
return true;
}
else
{
node->name = strdup(str_ptr);
return node->name && *node->name;
}
}
static struct rxml_node *rxml_parse_node(const char **ptr_)
{
const char *ptr = NULL;
const char *closing = NULL;
char *str = NULL;
bool is_closing = false;
struct rxml_node *node = (struct rxml_node*)calloc(1, sizeof(*node));
if (!node)
return NULL;
skip_spaces(ptr_);
ptr = *ptr_;
if (*ptr != '<')
goto error;
closing = strchr(ptr, '>');
if (!closing)
goto error;
str = strdup_range(ptr + 1, closing);
if (!str)
goto error;
if (!rxml_parse_tag(node, str))
goto error;
is_closing = strstr(ptr, "/>") + 1 == closing; // Are spaces between / and > allowed?
// Look for more data. Either child nodes or data.
if (!is_closing)
{
size_t closing_tag_size = strlen(node->name) + 4;
char *closing_tag = (char*)malloc(closing_tag_size);
const char *cdata_start = NULL;
const char *child_start = NULL;
const char *closing_start = NULL;
if (!closing_tag)
{
free(closing_tag);
goto error;
}
snprintf(closing_tag, closing_tag_size, "</%s>", node->name);
cdata_start = strstr(closing + 1, "<![CDATA[");
child_start = strchr(closing + 1, '<');
closing_start = strstr(closing + 1, closing_tag);
if (!closing_start)
{
free(closing_tag);
goto error;
}
if (cdata_start && range_is_space(closing + 1, cdata_start)) // CDATA section
{
const char *cdata_end = strstr(cdata_start, "]]>");
if (!cdata_end)
{
free(closing_tag);
goto error;
}
node->data = strdup_range(cdata_start + strlen("<![CDATA["), cdata_end);
}
else if (closing_start && closing_start == child_start) // Simple Data
node->data = strdup_range(closing + 1, closing_start);
else // Parse all child nodes.
{
struct rxml_node *list = NULL;
struct rxml_node *tail = NULL;
const char *ptr = child_start;
const char *first_start = strchr(ptr, '<');
const char *first_closing = strstr(ptr, "</");
while (first_start && first_closing && first_start < first_closing)
{
struct rxml_node *new_node = rxml_parse_node(&ptr);
if (!new_node)
{
free(closing_tag);
goto error;
}
if (tail)
{
tail->next = new_node;
tail = new_node;
}
else
list = tail = new_node;
first_start = strchr(ptr, '<');
first_closing = strstr(ptr, "</");
}
node->children = list;
closing_start = strstr(ptr, closing_tag);
if (!closing_start)
{
free(closing_tag);
goto error;
}
}
*ptr_ = closing_start + strlen(closing_tag);
free(closing_tag);
}
else
*ptr_ = closing + 1;
free(str);
return node;
error:
free(str);
rxml_free_node(node);
return NULL;
}
static char *purge_xml_comments(const char *str)
{
size_t len = strlen(str);
char *new_str = (char*)malloc(len + 1);
if (!new_str)
return NULL;
new_str[len] = '\0';
char *copy_dest = new_str;
const char *copy_src = str;
for (;;)
{
const char *comment_start = strstr(copy_src, "<!--");
const char *comment_end = strstr(copy_src, "-->");
if (!comment_start || !comment_end)
break;
ptrdiff_t copy_len = comment_start - copy_src;
memcpy(copy_dest, copy_src, copy_len);
copy_dest += copy_len;
copy_src = comment_end + strlen("-->");
}
// Avoid strcpy() as OpenBSD is anal and hates you for using it even when it's perfectly safe.
len = strlen(copy_src);
memcpy(copy_dest, copy_src, len);
copy_dest[len] = '\0';
return new_str;
}
rxml_document_t *rxml_load_document(const char *path)
{
#ifndef RXML_TEST
RARCH_WARN("Using RXML as drop in for libxml2. Behavior might be very buggy.\n");
#endif
char *memory_buffer = NULL;
char *new_memory_buffer = NULL;
const char *mem_ptr = NULL;
long len = 0;
FILE *file = fopen(path, "r");
if (!file)
return NULL;
rxml_document_t *doc = (rxml_document_t*)calloc(1, sizeof(*doc));
if (!doc)
goto error;
fseek(file, 0, SEEK_END);
len = ftell(file);
rewind(file);
memory_buffer = (char*)malloc(len + 1);
if (!memory_buffer)
goto error;
memory_buffer[len] = '\0';
if (fread(memory_buffer, 1, len, file) != (size_t)len)
goto error;
fclose(file);
file = NULL;
mem_ptr = memory_buffer;
if (!validate_header(&mem_ptr))
goto error;
new_memory_buffer = purge_xml_comments(mem_ptr);
if (!new_memory_buffer)
goto error;
free(memory_buffer);
mem_ptr = memory_buffer = new_memory_buffer;
doc->root_node = rxml_parse_node(&mem_ptr);
if (!doc->root_node)
goto error;
free(memory_buffer);
return doc;
error:
free(memory_buffer);
if (file)
fclose(file);
rxml_free_document(doc);
return NULL;
}
void rxml_free_document(rxml_document_t *doc)
{
if (!doc)
return;
if (doc->root_node)
rxml_free_node(doc->root_node);
free(doc);
}
char *rxml_node_attrib(struct rxml_node *node, const char *attrib)
{
for (struct rxml_attrib_node *attribs = node->attrib; attribs; attribs = attribs->next)
{
if (!strcmp(attrib, attribs->attrib))
return attribs->value;
}
return NULL;
}