ebclient/lib/libmxml/mmd.c
Jacques De SAGAN 03de9e18bb first import
2024-04-07 11:52:06 +08:00

979 lines
22 KiB
C

/*
* Implementation of miniature markdown library.
*
* https://github.com/michaelrsweet/mmd
*
* Copyright 2017 by Michael R Sweet.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions are met:
*
* 1. Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS "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 COPYRIGHT HOLDER OR CONTRIBUTORS 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.
*/
/*
* Include necessary headers...
*/
#include "mmd.h"
#include <stdlib.h>
#include <ctype.h>
#include <string.h>
/*
* Structures...
*/
struct _mmd_s
{
mmd_type_t type; /* Node type */
int whitespace; /* Leading whitespace? */
char *text, /* Text */
*url; /* Reference URL (image/link/etc.) */
mmd_t *parent, /* Parent node */
*first_child, /* First child node */
*last_child, /* Last child node */
*prev_sibling, /* Previous sibling node */
*next_sibling; /* Next sibling node */
};
/*
* Local functions...
*/
static mmd_t *mmd_add(mmd_t *parent, mmd_type_t type, int whitespace, char *text, char *url);
static void mmd_free(mmd_t *node);
static void mmd_parse_inline(mmd_t *parent, char *line);
static char *mmd_parse_link(char *lineptr, char **text, char **url);
static void mmd_remove(mmd_t *node);
/*
* 'mmdFree()' - Free a markdown tree.
*/
void
mmdFree(mmd_t *node) /* I - First node */
{
mmd_t *current, /* Current node */
*next; /* Next node */
mmd_remove(node);
for (current = node->first_child; current; current = next)
{
/*
* Get the next node...
*/
if ((next = current->first_child) != NULL)
{
/*
* Free parent nodes after child nodes have been freed...
*/
current->first_child = NULL;
continue;
}
if ((next = current->next_sibling) == NULL)
{
/*
* Next node is the parent, which we'll free as needed...
*/
if ((next = current->parent) == node)
next = NULL;
}
/*
* Free child...
*/
mmd_free(current);
}
/*
* Then free the memory used by the parent node...
*/
mmd_free(node);
}
/*
* 'mmdGetFirstChild()' - Return the first child of a node, if any.
*/
mmd_t * /* O - First child or @code NULL@ if none */
mmdGetFirstChild(mmd_t *node) /* I - Node */
{
return (node ? node->first_child : NULL);
}
/*
* 'mmdGetLastChild()' - Return the last child of a node, if any.
*/
mmd_t * /* O - Last child or @code NULL@ if none */
mmdGetLastChild(mmd_t *node) /* I - Node */
{
return (node ? node->last_child : NULL);
}
/*
* 'mmdGetMetadata()' - Return the metadata for the given keyword.
*/
const char * /* O - Value or @code NULL@ if none */
mmdGetMetadata(mmd_t *doc, /* I - Document */
const char *keyword) /* I - Keyword */
{
mmd_t *metadata, /* Metadata node */
*current; /* Current node */
char prefix[256]; /* Prefix string */
size_t prefix_len; /* Length of prefix string */
const char *value; /* Pointer to value */
if (!doc || (metadata = doc->first_child) == NULL || metadata->type != MMD_TYPE_METADATA)
return (NULL);
snprintf(prefix, sizeof(prefix), "%s:", keyword);
prefix_len = strlen(prefix);
for (current = metadata->first_child; current; current = current->next_sibling)
{
if (strncmp(current->text, prefix, prefix_len))
continue;
value = current->text + prefix_len;
while (isspace(*value & 255))
value ++;
return (value);
}
return (NULL);
}
/*
* 'mmdGetNextSibling()' - Return the next sibling of a node, if any.
*/
mmd_t * /* O - Next sibling or @code NULL@ if none */
mmdGetNextSibling(mmd_t *node) /* I - Node */
{
return (node ? node->next_sibling : NULL);
}
/*
* 'mmdGetParent()' - Return the parent of a node, if any.
*/
mmd_t * /* O - Parent node or @code NULL@ if none */
mmdGetParent(mmd_t *node) /* I - Node */
{
return (node ? node->parent : NULL);
}
/*
* 'mmdGetPrevSibling()' - Return the previous sibling of a node, if any.
*/
mmd_t * /* O - Previous sibling or @code NULL@ if none */
mmdGetPrevSibling(mmd_t *node) /* I - Node */
{
return (node ? node->prev_sibling : NULL);
}
/*
* 'mmdGetText()' - Return the text associated with a node, if any.
*/
const char * /* O - Text or @code NULL@ if none */
mmdGetText(mmd_t *node) /* I - Node */
{
return (node ? node->text : NULL);
}
/*
* 'mmdGetType()' - Return the type of a node, if any.
*/
mmd_type_t /* O - Type or @code MMD_TYPE_NONE@ if none */
mmdGetType(mmd_t *node) /* I - Node */
{
return (node ? node->type : MMD_TYPE_NONE);
}
/*
* 'mmdGetURL()' - Return the URL associated with a node, if any.
*/
const char * /* O - URL or @code NULL@ if none */
mmdGetURL(mmd_t *node) /* I - Node */
{
return (node ? node->url : NULL);
}
/*
* 'mmdGetWhitespace()' - Return whether whitespace preceded a node.
*/
int /* O - 1 for whitespace, 0 for none */
mmdGetWhitespace(mmd_t *node) /* I - Node */
{
return (node ? node->whitespace : 0);
}
/*
* 'mmdIsBlock()' - Return whether the node is a block.
*/
int /* O - 1 for block nodes, 0 otherwise */
mmdIsBlock(mmd_t *node) /* I - Node */
{
return (node ? node->type < MMD_TYPE_NORMAL_TEXT : 0);
}
/*
* 'mmdLoad()' - Load a markdown file into nodes.
*/
mmd_t * /* O - First node in markdown */
mmdLoad(const char *filename) /* I - File to load */
{
FILE *fp; /* File */
mmd_t *doc; /* Document */
/*
* Open the file and create an empty document...
*/
if ((fp = fopen(filename, "r")) == NULL)
return (NULL);
doc = mmdLoadFile(fp);
fclose(fp);
return (doc);
}
/*
* 'mmdLoadFile()' - Load a markdown file into nodes from a stdio file.
*/
mmd_t * /* O - First node in markdown */
mmdLoadFile(FILE *fp) /* I - File to load */
{
mmd_t *doc, /* Document */
*current, /* Current parent block */
*block = NULL; /* Current block */
mmd_type_t type; /* Type for line */
char line[65536], /* Line from file */
*lineptr, /* Pointer into line */
*lineend; /* End of line */
int blank_code = 0; /* Saved indented blank code line */
/*
* Create an empty document...
*/
doc = current = mmd_add(NULL, MMD_TYPE_DOCUMENT, 0, NULL, NULL);
if (!doc)
{
fclose(fp);
return (NULL);
}
/*
* Read lines until end-of-file...
*/
while (fgets(line, sizeof(line), fp))
{
lineptr = line;
while (isspace(*lineptr & 255))
lineptr ++;
if ((lineptr - line) >= 4 && !block && (current == doc || current->type == MMD_TYPE_CODE_BLOCK))
{
/*
* Indented code block.
*/
if (current == doc)
current = mmd_add(doc, MMD_TYPE_CODE_BLOCK, 0, NULL, NULL);
if (blank_code)
mmd_add(current, MMD_TYPE_CODE_TEXT, 0, "\n", NULL);
mmd_add(current, MMD_TYPE_CODE_TEXT, 0, line + 4, NULL);
blank_code = 0;
continue;
}
else if (*lineptr == '`' && (!lineptr[1] || lineptr[1] == '`'))
{
if (block)
{
if (block->type == MMD_TYPE_CODE_BLOCK)
block = NULL;
else if (block->type == MMD_TYPE_LIST_ITEM)
block = mmd_add(block, MMD_TYPE_CODE_BLOCK, 0, NULL, NULL);
else if (block->parent->type == MMD_TYPE_LIST_ITEM)
block = mmd_add(block->parent, MMD_TYPE_CODE_BLOCK, 0, NULL, NULL);
else
block = mmd_add(current, MMD_TYPE_CODE_BLOCK, 0, NULL, NULL);
}
else
block = mmd_add(current, MMD_TYPE_CODE_BLOCK, 0, NULL, NULL);
continue;
}
if (block && block->type == MMD_TYPE_CODE_BLOCK)
{
mmd_add(block, MMD_TYPE_CODE_TEXT, 0, line, NULL);
continue;
}
else if (!strncmp(lineptr, "---", 3) && doc->first_child == NULL)
{
/*
* Document metadata...
*/
block = mmd_add(doc, MMD_TYPE_METADATA, 0, NULL, NULL);
while (fgets(line, sizeof(line), fp))
{
lineptr = line;
while (isspace(*lineptr & 255))
lineptr ++;
if (!strncmp(line, "---", 3) || !strncmp(line, "...", 3))
break;
lineend = lineptr + strlen(lineptr) - 1;
if (lineend > lineptr && *lineend == '\n')
*lineend = '\0';
mmd_add(block, MMD_TYPE_METADATA_TEXT, 0, lineptr, NULL);
}
block = NULL;
continue;
}
else if (!block && (!strncmp(lineptr, "---", 3) || !strncmp(lineptr, "***", 3) || !strncmp(lineptr, "___", 3)))
{
int ch = *lineptr;
lineptr += 3;
while (*lineptr && (*lineptr == ch || isspace(*lineptr & 255)))
lineptr ++;
if (!*lineptr)
{
block = NULL;
mmd_add(current, MMD_TYPE_THEMATIC_BREAK, 0, NULL, NULL);
continue;
}
}
if (*lineptr == '>')
{
/*
* Block quote. See if the parent of the current node is already a block
* quote...
*/
if (current == doc || current->type != MMD_TYPE_BLOCK_QUOTE)
current = mmd_add(doc, MMD_TYPE_BLOCK_QUOTE, 0, NULL, NULL);
/*
* Skip whitespace after the ">"...
*/
lineptr ++;
while (isspace(*lineptr & 255))
lineptr ++;
}
else if (current->type == MMD_TYPE_BLOCK_QUOTE)
current = current->parent;
if (!*lineptr)
{
blank_code = current->type == MMD_TYPE_CODE_BLOCK;
block = NULL;
continue;
}
else if (!strcmp(lineptr, "+"))
{
if (block)
{
if (block->type == MMD_TYPE_LIST_ITEM)
block = mmd_add(block, MMD_TYPE_PARAGRAPH, 0, NULL, NULL);
else if (block->parent->type == MMD_TYPE_LIST_ITEM)
block = mmd_add(block->parent, MMD_TYPE_PARAGRAPH, 0, NULL, NULL);
else
block = NULL;
}
continue;
}
else if (block && block->type == MMD_TYPE_PARAGRAPH && (!strncmp(lineptr, "---", 3) || !strncmp(lineptr, "===", 3)))
{
int ch = *lineptr;
lineptr += 3;
while (*lineptr == ch)
lineptr ++;
while (isspace(*lineptr & 255))
lineptr ++;
if (!*lineptr)
{
if (ch == '=')
block->type = MMD_TYPE_HEADING_1;
else
block->type = MMD_TYPE_HEADING_2;
block = NULL;
continue;
}
type = MMD_TYPE_PARAGRAPH;
}
else if ((*lineptr == '-' || *lineptr == '+' || *lineptr == '*') && isspace(lineptr[1] & 255))
{
/*
* Bulleted list...
*/
lineptr += 2;
while (isspace(*lineptr & 255))
lineptr ++;
if (current == doc && doc->last_child && doc->last_child->type == MMD_TYPE_UNORDERED_LIST)
current = doc->last_child;
else if (current->type != MMD_TYPE_UNORDERED_LIST)
current = mmd_add(current, MMD_TYPE_UNORDERED_LIST, 0, NULL, NULL);
type = MMD_TYPE_LIST_ITEM;
block = NULL;
}
else if (isdigit(*lineptr & 255))
{
/*
* Ordered list?
*/
char *temp = lineptr + 1;
while (isdigit(*temp & 255))
temp ++;
if (*temp == '.' && isspace(temp[1] & 255))
{
/*
* Yes, ordered list.
*/
lineptr = temp + 2;
while (isspace(*lineptr & 255))
lineptr ++;
if (current == doc && doc->last_child && doc->last_child->type == MMD_TYPE_ORDERED_LIST)
current = doc->last_child;
else if (current->type != MMD_TYPE_ORDERED_LIST)
current = mmd_add(current, MMD_TYPE_ORDERED_LIST, 0, NULL, NULL);
type = MMD_TYPE_LIST_ITEM;
block = NULL;
}
else
{
/*
* No, just a regular paragraph...
*/
type = block ? block->type : MMD_TYPE_PARAGRAPH;
}
}
else if (*lineptr == '#')
{
/*
* Heading, count the number of '#' for the heading level...
*/
char *temp = lineptr + 1;
while (*temp == '#')
temp ++;
if ((temp - lineptr) <= 6)
{
/*
* Heading 1-6...
*/
type = MMD_TYPE_HEADING_1 + (temp - lineptr - 1);
block = NULL;
/*
* Skip whitespace after "#"...
*/
lineptr = temp;
while (isspace(*lineptr & 255))
lineptr ++;
/*
* Strip trailing "#" characters...
*/
for (temp = lineptr + strlen(lineptr) - 1; temp > lineptr && *temp == '#'; temp --)
*temp = '\0';
}
else
{
/*
* More than 6 #'s, just treat as a paragraph...
*/
type = MMD_TYPE_PARAGRAPH;
}
if (current->type != MMD_TYPE_BLOCK_QUOTE)
current = doc;
}
else if (!block)
{
type = MMD_TYPE_PARAGRAPH;
if (lineptr == line)
current = doc;
}
else
type = block->type;
if (!block || block->type != type)
{
if (current->type == MMD_TYPE_CODE_BLOCK)
current = doc;
block = mmd_add(current, type, 0, NULL, NULL);
}
mmd_parse_inline(block, lineptr);
}
return (doc);
}
/*
* 'mmd_add()' - Add a new markdown node.
*/
static mmd_t * /* O - New node */
mmd_add(mmd_t *parent, /* I - Parent node */
mmd_type_t type, /* I - Node type */
int whitespace, /* I - 1 if whitespace precedes this node */
char *text, /* I - Text, if any */
char *url) /* I - URL, if any */
{
mmd_t *temp; /* New node */
if ((temp = calloc(1, sizeof(mmd_t))) != NULL)
{
if (parent)
{
/*
* Add node to the parent...
*/
temp->parent = parent;
if (parent->last_child)
{
parent->last_child->next_sibling = temp;
temp->prev_sibling = parent->last_child;
parent->last_child = temp;
}
else
{
parent->first_child = parent->last_child = temp;
}
}
/*
* Copy the node values...
*/
temp->type = type;
temp->whitespace = whitespace;
if (text)
temp->text = strdup(text);
if (url)
temp->url = strdup(url);
}
return (temp);
}
/*
* 'mmd_free()' - Free memory used by a node.
*/
static void
mmd_free(mmd_t *node) /* I - Node */
{
if (node->text)
free(node->text);
if (node->url)
free(node->url);
free(node);
}
/*
* 'mmd_parse_inline()' - Parse inline formatting.
*/
static void
mmd_parse_inline(mmd_t *parent, /* I - Parent node */
char *line) /* I - Line from file */
{
mmd_type_t type; /* Current node type */
int whitespace; /* Whitespace precedes? */
char *lineptr, /* Pointer into line */
*text, /* Text fragment in line */
*url; /* URL in link */
whitespace = parent->last_child != NULL;
for (lineptr = line, text = NULL, type = MMD_TYPE_NORMAL_TEXT; *lineptr; lineptr ++)
{
if (isspace(*lineptr & 255) && type != MMD_TYPE_CODE_TEXT)
{
if (text)
{
*lineptr = '\0';
mmd_add(parent, type, whitespace, text, NULL);
text = NULL;
}
whitespace = 1;
}
else if (*lineptr == '!' && lineptr[1] == '[' && type != MMD_TYPE_CODE_TEXT)
{
/*
* Image...
*/
if (text)
{
mmd_add(parent, type, whitespace, text, NULL);
text = NULL;
whitespace = 0;
}
lineptr = mmd_parse_link(lineptr + 1, &text, &url);
if (url)
mmd_add(parent, MMD_TYPE_IMAGE, whitespace, text, url);
if (!*lineptr)
return;
text = url = NULL;
whitespace = 0;
lineptr --;
}
else if (*lineptr == '[' && type != MMD_TYPE_CODE_TEXT)
{
/*
* Link...
*/
if (text)
{
mmd_add(parent, type, whitespace, text, NULL);
text = NULL;
whitespace = 0;
}
lineptr = mmd_parse_link(lineptr, &text, &url);
if (text && *text == '`')
{
char *end = text + strlen(text) - 1;
text ++;
if (end > text && *end == '`')
*end = '\0';
mmd_add(parent, MMD_TYPE_CODE_TEXT, whitespace, text, url);
}
else if (text)
mmd_add(parent, MMD_TYPE_LINKED_TEXT, whitespace, text, url);
if (!*lineptr)
return;
text = url = NULL;
whitespace = 0;
lineptr --;
}
else if (*lineptr == '<' && type != MMD_TYPE_CODE_TEXT && strchr(lineptr + 1, '>'))
{
/*
* Autolink...
*/
if (text)
{
mmd_add(parent, type, whitespace, text, NULL);
text = NULL;
whitespace = 0;
}
url = lineptr + 1;
lineptr = strchr(lineptr + 1, '>');
*lineptr++ = '\0';
mmd_add(parent, MMD_TYPE_LINKED_TEXT, whitespace, url, url);
text = url = NULL;
whitespace = 0;
lineptr --;
}
else if (*lineptr == '*' && type != MMD_TYPE_CODE_TEXT)
{
if (text)
{
*lineptr = '\0';
mmd_add(parent, type, whitespace, text, NULL);
*lineptr = '*';
text = NULL;
whitespace = 0;
}
if (type == MMD_TYPE_NORMAL_TEXT)
{
if (lineptr[1] == '*' && !isspace(lineptr[2] & 255))
{
type = MMD_TYPE_STRONG_TEXT;
lineptr ++;
}
else if (!isspace(lineptr[1] & 255))
{
type = MMD_TYPE_EMPHASIZED_TEXT;
}
text = lineptr + 1;
}
else
{
if (lineptr[1] == '*')
lineptr ++;
type = MMD_TYPE_NORMAL_TEXT;
}
}
else if (*lineptr == '`')
{
if (text)
{
*lineptr = '\0';
mmd_add(parent, type, whitespace, text, NULL);
text = NULL;
whitespace = 0;
}
if (type == MMD_TYPE_CODE_TEXT)
{
type = MMD_TYPE_NORMAL_TEXT;
}
else
{
type = MMD_TYPE_CODE_TEXT;
text = lineptr + 1;
}
}
else if (!text)
{
if (*lineptr == '\\' && lineptr[1])
{
/*
* Escaped character...
*/
lineptr ++;
}
text = lineptr;
}
else if (*lineptr == '\\' && lineptr[1])
{
/*
* Escaped character...
*/
memmove(lineptr, lineptr + 1, strlen(lineptr));
}
}
if (text)
mmd_add(parent, type, whitespace, text, NULL);
}
/*
* 'mmd_parse_link()' - Parse a link.
*/
static char * /* O - End of link text */
mmd_parse_link(char *lineptr, /* I - Pointer into line */
char **text, /* O - Text */
char **url) /* O - URL */
{
lineptr ++; /* skip "[" */
*text = lineptr;
*url = NULL;
while (*lineptr && *lineptr != ']')
{
if (*lineptr == '\"')
{
lineptr ++;
while (*lineptr && *lineptr != '\"')
lineptr ++;
if (!*lineptr)
return (lineptr);
}
lineptr ++;
}
if (!*lineptr)
return (lineptr);
*lineptr++ = '\0';
while (isspace(*lineptr & 255))
lineptr ++;
if (*lineptr == '(')
{
/*
* Get URL...
*/
lineptr ++;
*url = lineptr;
while (*lineptr && *lineptr != ')')
{
if (isspace(*lineptr & 255))
*lineptr = '\0';
else if (*lineptr == '\"')
{
lineptr ++;
while (*lineptr && *lineptr != '\"')
lineptr ++;
if (!*lineptr)
return (lineptr);
}
lineptr ++;
}
*lineptr++ = '\0';
}
return (lineptr);
}
/*
* 'mmd_remove()' - Remove a node from its parent.
*/
static void
mmd_remove(mmd_t *node) /* I - Node */
{
if (node->parent)
{
if (node->prev_sibling)
node->prev_sibling->next_sibling = node->next_sibling;
else
node->parent->first_child = node->next_sibling;
if (node->next_sibling)
node->next_sibling->prev_sibling = node->prev_sibling;
else
node->parent->last_child = node->prev_sibling;
node->parent = NULL;
node->prev_sibling = NULL;
node->next_sibling = NULL;
}
}