xslt.c 8.02 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"
Philipp Schafft's avatar
Philipp Schafft committed
53
#include "util.h"
54

55
#define CATMODULE "xslt"
Karl Heyes's avatar
Karl Heyes committed
56

57 58 59 60 61 62 63 64 65
#include "logging.h"

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

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 91
#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

92 93 94
/* Keep it small... */
#define CACHESIZE 3

95 96
static stylesheet_cache_t cache[CACHESIZE];
static mutex_t xsltlock;
97

98
void xslt_initialize(void)
99 100 101
{
    memset(cache, 0, sizeof(stylesheet_cache_t)*CACHESIZE);
    thread_mutex_create(&xsltlock);
102 103
    xmlInitParser();
    LIBXML_TEST_VERSION
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
    xmlCleanupParser();
120 121 122
    xsltCleanupGlobals();
}

123
static int evict_cache_entry(void) {
brendan's avatar
brendan committed
124
    int i, age=0, oldest=0;
125 126 127 128 129 130 131 132 133 134 135 136 137 138

    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;
}

139
static xsltStylesheetPtr xslt_get_stylesheet(const char *fn) {
140 141 142 143 144
    int i;
    int empty = -1;
    struct stat file;

    if(stat(fn, &file)) {
145
        ICECAST_LOG_WARN("Error checking for stylesheet file \"%s\": %s", fn, 
146
                strerror(errno));
147 148 149 150 151 152
        return NULL;
    }

    for(i=0; i < CACHESIZE; i++) {
        if(cache[i].filename)
        {
153 154 155
#ifdef _WIN32
            if(!stricmp(fn, cache[i].filename))
#else
156
            if(!strcmp(fn, cache[i].filename))
157
#endif
158 159 160 161 162 163
            {
                if(file.st_mtime > cache[i].last_modified)
                {
                    xsltFreeStylesheet(cache[i].stylesheet);

                    cache[i].last_modified = file.st_mtime;
164
                    cache[i].stylesheet = xsltParseStylesheetFile (XMLSTR(fn));
165 166
                    cache[i].cache_age = time(NULL);
                }
167
                ICECAST_LOG_DEBUG("Using cached sheet %i", i);
168 169 170 171 172 173 174 175 176 177 178 179 180 181
                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);
182
    cache[i].stylesheet = xsltParseStylesheetFile (XMLSTR(fn));
183 184 185
    cache[i].cache_age = time(NULL);
    return cache[i].stylesheet;
}
186

187
void xslt_transform(xmlDocPtr doc, const char *xslfilename, client_t *client)
188
{
189 190
    xmlDocPtr    res;
    xsltStylesheetPtr cur;
191
    xmlChar *string;
192
    int len, problem = 0;
193
    const char *mediatype = NULL;
194
    const char *charset = NULL;
195

196 197 198
    xmlSetGenericErrorFunc ("", log_parse_failure);
    xsltSetGenericErrorFunc ("", log_parse_failure);

199 200 201
    thread_mutex_lock(&xsltlock);
    cur = xslt_get_stylesheet(xslfilename);

202 203
    if (cur == NULL)
    {
204
        thread_mutex_unlock(&xsltlock);
205
        ICECAST_LOG_ERROR("problem reading stylesheet \"%s\"", xslfilename);
206
        client_send_404 (client, "Could not parse XSLT file");
207
        return;
208
    }
209

210
    res = xsltApplyStylesheet(cur, doc, NULL);
211 212 213 214
    if (res != NULL) {
        if (xsltSaveResultToString(&string, &len, res, cur) < 0)
            problem = 1;
    } else {
215
        problem = 1;
216
    }
217

218 219 220 221
    /* lets find out the content type and character encoding to use */
    if (cur->encoding)
       charset = (char *)cur->encoding;

222 223 224 225 226
    if (cur->mediaType)
        mediatype = (char *)cur->mediaType;
    else
    {
        /* check method for the default, a missing method assumes xml */
227
        if (cur->method && xmlStrcmp (cur->method, XMLSTR("html")) == 0)
228 229
            mediatype = "text/html";
        else
230
            if (cur->method && xmlStrcmp (cur->method, XMLSTR("text")) == 0)
231 232 233 234
                mediatype = "text/plain";
            else
                mediatype = "text/xml";
    }
235
    if (problem == 0)
236
    {
ePirat's avatar
ePirat committed
237 238 239
        ssize_t ret;
        int failed = 0;
        refbuf_t *refbuf;
240 241 242
        size_t full_len = strlen (mediatype) + len + 1024;
        if (full_len < 4096)
            full_len = 4096;
ePirat's avatar
ePirat committed
243
        refbuf = refbuf_new (full_len);
244

245
        if (string == NULL)
246
            string = xmlCharStrdup ("");
247
        ret = util_http_build_header(refbuf->data, full_len, 0, 0, 200, NULL, mediatype, charset, NULL, NULL);
248 249 250 251 252 253 254 255 256 257 258 259 260 261 262 263 264 265 266 267 268 269 270 271 272 273 274 275 276 277 278 279 280 281 282
        if (ret == -1) {
            ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
            client_send_500(client, "Header generation failed.");
        } else {
            if ( full_len < (ret + len + 64) ) {
                void *new_data;
                full_len = ret + len + 64;
                new_data = realloc(refbuf->data, full_len);
                if (new_data) {
                    ICECAST_LOG_DEBUG("Client buffer reallocation succeeded.");
                    refbuf->data = new_data;
                    refbuf->len = full_len;
                    ret = util_http_build_header(refbuf->data, full_len, 0, 0, 200, NULL, mediatype, charset, NULL, NULL);
                    if (ret == -1) {
                        ICECAST_LOG_ERROR("Dropping client as we can not build response headers.");
                        client_send_500(client, "Header generation failed.");
                        failed = 1;
                    }
                } else {
                    ICECAST_LOG_ERROR("Client buffer reallocation failed. Dropping client.");
                    client_send_500(client, "Buffer reallocation failed.");
                    failed = 1;
                }
            }

            if (!failed) {
                  snprintf(refbuf->data + ret, full_len - ret, "Content-Length: %d\r\n\r\n%s", len, string);

                client->respcode = 200;
                client_set_queue (client, NULL);
                client->refbuf = refbuf;
                refbuf->len = strlen (refbuf->data);
                fserve_add_client (client, NULL);
            }
        }
283 284
        xmlFree (string);
    }
285 286
    else
    {
287
        ICECAST_LOG_WARN("problem applying stylesheet \"%s\"", xslfilename);
288 289
        client_send_404 (client, "XSLT problem");
    }
290
    thread_mutex_unlock (&xsltlock);
291 292 293
    xmlFreeDoc(res);
}