xslt.c 6.38 KB
Newer Older
1 2 3 4 5 6 7 8 9 10 11 12
/* Icecast
 *
 * This program is distributed under the GNU General Public License, version 2.
 * A copy of this license is included with this source.
 *
 * Copyright 2000-2004, Jack Moffitt <jack@xiph.org, 
 *                      Michael Smith <msmith@xiph.org>,
 *                      oddsock <oddsock@xiph.org>,
 *                      Karl Heyes <karl@xiph.org>
 *                      and others (see AUTHORS for details).
 */

13 14 15 16
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif

17 18 19 20 21 22 23 24 25 26 27 28
#include <string.h>
#include <libxml/xmlmemory.h>
#include <libxml/debugXML.h>
#include <libxml/HTMLtree.h>
#include <libxml/xmlIO.h>
#include <libxml/xinclude.h>
#include <libxml/catalog.h>
#include <libxslt/xslt.h>
#include <libxslt/xsltInternals.h>
#include <libxslt/transform.h>
#include <libxslt/xsltutils.h>

29 30 31 32
#include <sys/types.h>
#include <sys/stat.h>
#include <errno.h>

33
#ifdef  HAVE_SYS_TIME_H
34 35 36
#include <sys/time.h>
#endif

37 38 39
#ifdef WIN32
#define snprintf _snprintf
#endif
40

Karl Heyes's avatar
Karl Heyes committed
41 42 43 44
#include "thread/thread.h"
#include "avl/avl.h"
#include "httpp/httpp.h"
#include "net/sock.h"
45 46 47 48 49 50 51

#include "connection.h"

#include "global.h"
#include "refbuf.h"
#include "client.h"
#include "stats.h"
52
#include "fserve.h"
53

54
#define CATMODULE "xslt"
Karl Heyes's avatar
Karl Heyes committed
55

56 57 58 59 60 61 62 63 64
#include "logging.h"

typedef struct {
    char              *filename;
    time_t             last_modified;
    time_t             cache_age;
    xsltStylesheetPtr  stylesheet;
} stylesheet_cache_t;

65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90
#ifndef HAVE_XSLTSAVERESULTTOSTRING
int xsltSaveResultToString(xmlChar **doc_txt_ptr, int * doc_txt_len, xmlDocPtr result, xsltStylesheetPtr style) {
    xmlOutputBufferPtr buf;

    *doc_txt_ptr = NULL;
    *doc_txt_len = 0;
    if (result->children == NULL)
	return(0);

	buf = xmlAllocOutputBuffer(NULL);

    if (buf == NULL)
		return(-1);
    xsltSaveResultTo(buf, result, style);
    if (buf->conv != NULL) {
		*doc_txt_len = buf->conv->use;
		*doc_txt_ptr = xmlStrndup(buf->conv->content, *doc_txt_len);
    } else {
		*doc_txt_len = buf->buffer->use;
		*doc_txt_ptr = xmlStrndup(buf->buffer->content, *doc_txt_len);
    }
    (void)xmlOutputBufferClose(buf);
    return 0;
}
#endif

91 92 93
/* Keep it small... */
#define CACHESIZE 3

94 95
static stylesheet_cache_t cache[CACHESIZE];
static mutex_t xsltlock;
96

97
void xslt_initialize(void)
98
{
99 100 101
    xmlSubstituteEntitiesDefault(1);
    xmlLoadExtDtdDefaultValue = 1;

102 103
    memset(cache, 0, sizeof(stylesheet_cache_t)*CACHESIZE);
    thread_mutex_create(&xsltlock);
104 105
    xmlSubstituteEntitiesDefault(1);
    xmlLoadExtDtdDefaultValue = 1;
106 107
}

108
void xslt_shutdown(void) {
109 110 111 112 113 114 115 116 117
    int i;

    for(i=0; i < CACHESIZE; i++) {
        if(cache[i].filename)
            free(cache[i].filename);
        if(cache[i].stylesheet)
            xsltFreeStylesheet(cache[i].stylesheet);
    }

118
    thread_mutex_destroy (&xsltlock);
119 120 121
    xsltCleanupGlobals();
}

122
static int evict_cache_entry(void) {
brendan's avatar
brendan committed
123
    int i, age=0, oldest=0;
124 125 126 127 128 129 130 131 132 133 134 135 136 137

    for(i=0; i < CACHESIZE; i++) {
        if(cache[i].cache_age > age) {
            age = cache[i].cache_age;
            oldest = i;
        }
    }

    xsltFreeStylesheet(cache[oldest].stylesheet);
    free(cache[oldest].filename);

    return oldest;
}

138
static xsltStylesheetPtr xslt_get_stylesheet(const char *fn) {
139 140 141 142 143
    int i;
    int empty = -1;
    struct stat file;

    if(stat(fn, &file)) {
144 145
        WARN2("Error checking for stylesheet file \"%s\": %s", fn, 
                strerror(errno));
146 147 148 149 150 151
        return NULL;
    }

    for(i=0; i < CACHESIZE; i++) {
        if(cache[i].filename)
        {
152 153 154
#ifdef _WIN32
            if(!stricmp(fn, cache[i].filename))
#else
155
            if(!strcmp(fn, cache[i].filename))
156
#endif
157 158 159 160 161 162
            {
                if(file.st_mtime > cache[i].last_modified)
                {
                    xsltFreeStylesheet(cache[i].stylesheet);

                    cache[i].last_modified = file.st_mtime;
163
                    cache[i].stylesheet = xsltParseStylesheetFile (XMLSTR(fn));
164 165
                    cache[i].cache_age = time(NULL);
                }
166
                DEBUG1("Using cached sheet %i", i);
167 168 169 170 171 172 173 174 175 176 177 178 179 180
                return cache[i].stylesheet;
            }
        }
        else
            empty = i;
    }

    if(empty>=0)
        i = empty;
    else
        i = evict_cache_entry();

    cache[i].last_modified = file.st_mtime;
    cache[i].filename = strdup(fn);
181
    cache[i].stylesheet = xsltParseStylesheetFile (XMLSTR(fn));
182 183 184
    cache[i].cache_age = time(NULL);
    return cache[i].stylesheet;
}
185

186
void xslt_transform(xmlDocPtr doc, const char *xslfilename, client_t *client)
187
{
188 189
    xmlDocPtr    res;
    xsltStylesheetPtr cur;
190
    xmlChar *string;
191
    int len, problem = 0;
192
    const char *mediatype = NULL;
193

194 195 196
    xmlSetGenericErrorFunc ("", log_parse_failure);
    xsltSetGenericErrorFunc ("", log_parse_failure);

197 198 199
    thread_mutex_lock(&xsltlock);
    cur = xslt_get_stylesheet(xslfilename);

200 201
    if (cur == NULL)
    {
202
        thread_mutex_unlock(&xsltlock);
203 204
        ERROR1 ("problem reading stylesheet \"%s\"", xslfilename);
        client_send_404 (client, "Could not parse XSLT file");
205
        return;
206
    }
207

208
    res = xsltApplyStylesheet(cur, doc, NULL);
209

210 211
    if (xsltSaveResultToString (&string, &len, res, cur) < 0)
        problem = 1;
212 213 214 215 216 217 218

    /* lets find out the content type to use */
    if (cur->mediaType)
        mediatype = (char *)cur->mediaType;
    else
    {
        /* check method for the default, a missing method assumes xml */
219
        if (cur->method && xmlStrcmp (cur->method, XMLSTR("html")) == 0)
220 221
            mediatype = "text/html";
        else
222
            if (cur->method && xmlStrcmp (cur->method, XMLSTR("text")) == 0)
223 224 225 226
                mediatype = "text/plain";
            else
                mediatype = "text/xml";
    }
227
    if (problem == 0)
228
    {
229 230 231
        /* the 100 is to allow for the hardcoded headers */
        unsigned int full_len = strlen (mediatype) + len + 100;
        refbuf_t *refbuf = refbuf_new (full_len);
232

233
        if (string == NULL)
234 235 236 237 238
            string = xmlCharStrdup ("");
        snprintf (refbuf->data, full_len,
                "HTTP/1.0 200 OK\r\nContent-Type: %s\r\nContent-Length: %d\r\n\r\n%s",
                mediatype, len, string);

239
        client->respcode = 200;
240
        client_set_queue (client, NULL);
241 242
        client->refbuf = refbuf;
        refbuf->len = strlen (refbuf->data);
243 244 245
        fserve_add_client (client, NULL);
        xmlFree (string);
    }
246 247 248 249 250
    else
    {
        WARN1 ("problem applying stylesheet \"%s\"", xslfilename);
        client_send_404 (client, "XSLT problem");
    }
251
    thread_mutex_unlock (&xsltlock);
252 253 254
    xmlFreeDoc(res);
}