modules/luci-base/src/template_parser.c

   1 /*
   2  * LuCI Template - Parser implementation
   3  *
   4  *   Copyright (C) 2009-2012 Jo-Philipp Wich <xm@subsignal.org>
   5  *
   6  *  Licensed under the Apache License, Version 2.0 (the "License");
   7  *  you may not use this file except in compliance with the License.
   8  *  You may obtain a copy of the License at
   9  *
  10  *      http://www.apache.org/licenses/LICENSE-2.0
  11  *
  12  *  Unless required by applicable law or agreed to in writing, software
  13  *  distributed under the License is distributed on an "AS IS" BASIS,
  14  *  WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  15  *  See the License for the specific language governing permissions and
  16  *  limitations under the License.
  17  */
  18
  19 #include "template_parser.h"
  20 #include "template_utils.h"
  21 #include "template_lmo.h"
  22
  23
  24 /* leading and trailing code for different types */
  25 const char *gen_code[9][2] = {
  26         { NULL,                                 NULL                    },
  27         { "write(\"",                   "\")"                   },
  28         { NULL,                                 NULL                    },
  29         { "write(tostring(",    " or \"\"))"    },
  30         { "include(\"",                 "\")"                   },
  31         { "write(\"",                   "\")"                   },
  32         { "write(\"",                   "\")"                   },
  33         { NULL,                                 " "                             },
  34         { NULL,                                 NULL                    },
  35 };
  36
  37 /* Simple strstr() like function that takes len arguments for both haystack and needle. */
  38 static char *strfind(char *haystack, int hslen, const char *needle, int ndlen)
  39 {
  40         int match = 0;
  41         int i, j;
  42
  43         for( i = 0; i < hslen; i++ )
  44         {
  45                 if( haystack[i] == needle[0] )
  46                 {
  47                         match = ((ndlen == 1) || ((i + ndlen) <= hslen));
  48
  49                         for( j = 1; (j < ndlen) && ((i + j) < hslen); j++ )
  50                         {
  51                                 if( haystack[i+j] != needle[j] )
  52                                 {
  53                                         match = 0;
  54                                         break;
  55                                 }
  56                         }
  57
  58                         if( match )
  59                                 return &haystack[i];
  60                 }
  61         }
  62
  63         return NULL;
  64 }
  65
  66 struct template_parser * template_open(const char *file)
  67 {
  68         struct stat s;
  69         struct template_parser *parser;
  70
  71         if (!(parser = malloc(sizeof(*parser))))
  72                 goto err;
  73
  74         memset(parser, 0, sizeof(*parser));
  75         parser->fd = -1;
  76         parser->file = file;
  77
  78         if (stat(file, &s))
  79                 goto err;
  80
  81         if ((parser->fd = open(file, O_RDONLY)) < 0)
  82                 goto err;
  83
  84         parser->size = s.st_size;
  85         parser->data = mmap(NULL, parser->size, PROT_READ, MAP_PRIVATE,
  86                                                 parser->fd, 0);
  87
  88         if (parser->data != MAP_FAILED)
  89         {
  90                 parser->off = parser->data;
  91                 parser->cur_chunk.type = T_TYPE_INIT;
  92                 parser->cur_chunk.s    = parser->data;
  93                 parser->cur_chunk.e    = parser->data;
  94
  95                 return parser;
  96         }
  97
  98 err:
  99         template_close(parser);
 100         return NULL;
 101 }
 102
 103 struct template_parser * template_string(const char *str, uint32_t len)
 104 {
 105         struct template_parser *parser;
 106
 107         if (!str) {
 108                 errno = EINVAL;
 109                 goto err;
 110         }
 111
 112         if (!(parser = malloc(sizeof(*parser))))
 113                 goto err;
 114
 115         memset(parser, 0, sizeof(*parser));
 116         parser->fd = -1;
 117
 118         parser->size = len;
 119         parser->data = (char*)str;
 120
 121         parser->off = parser->data;
 122         parser->cur_chunk.type = T_TYPE_INIT;
 123         parser->cur_chunk.s    = parser->data;
 124         parser->cur_chunk.e    = parser->data;
 125
 126         return parser;
 127
 128 err:
 129         template_close(parser);
 130         return NULL;
 131 }
 132
 133 void template_close(struct template_parser *parser)
 134 {
 135         if (!parser)
 136                 return;
 137
 138         if (parser->gc != NULL)
 139                 free(parser->gc);
 140
 141         /* if file is not set, we were parsing a string */
 142         if (parser->file) {
 143                 if ((parser->data != NULL) && (parser->data != MAP_FAILED))
 144                         munmap(parser->data, parser->size);
 145
 146                 if (parser->fd >= 0)
 147                         close(parser->fd);
 148         }
 149
 150         free(parser);
 151 }
 152
 153 void template_text(struct template_parser *parser, const char *e)
 154 {
 155         const char *s = parser->off;
 156
 157         if (s < (parser->data + parser->size))
 158         {
 159                 if (parser->strip_after)
 160                 {
 161                         while ((s <= e) && isspace(*s))
 162                                 s++;
 163                 }
 164
 165                 parser->cur_chunk.type = T_TYPE_TEXT;
 166         }
 167         else
 168         {
 169                 parser->cur_chunk.type = T_TYPE_EOF;
 170         }
 171
 172         parser->cur_chunk.line = parser->line;
 173         parser->cur_chunk.s = s;
 174         parser->cur_chunk.e = e;
 175 }
 176
 177 void template_code(struct template_parser *parser, const char *e)
 178 {
 179         const char *s = parser->off;
 180
 181         parser->strip_before = 0;
 182         parser->strip_after = 0;
 183
 184         if (*s == '-')
 185         {
 186                 parser->strip_before = 1;
 187                 for (s++; (s <= e) && (*s == ' ' || *s == '\t'); s++);
 188         }
 189
 190         if (*(e-1) == '-')
 191         {
 192                 parser->strip_after = 1;
 193                 for (e--; (e >= s) && (*e == ' ' || *e == '\t'); e--);
 194         }
 195
 196         switch (*s)
 197         {
 198                 /* comment */
 199                 case '#':
 200                         s++;
 201                         parser->cur_chunk.type = T_TYPE_COMMENT;
 202                         break;
 203
 204                 /* include */
 205                 case '+':
 206                         s++;
 207                         parser->cur_chunk.type = T_TYPE_INCLUDE;
 208                         break;
 209
 210                 /* translate */
 211                 case ':':
 212                         s++;
 213                         parser->cur_chunk.type = T_TYPE_I18N;
 214                         break;
 215
 216                 /* translate raw */
 217                 case '_':
 218                         s++;
 219                         parser->cur_chunk.type = T_TYPE_I18N_RAW;
 220                         break;
 221
 222                 /* expr */
 223                 case '=':
 224                         s++;
 225                         parser->cur_chunk.type = T_TYPE_EXPR;
 226                         break;
 227
 228                 /* code */
 229                 default:
 230                         parser->cur_chunk.type = T_TYPE_CODE;
 231                         break;
 232         }
 233
 234         parser->cur_chunk.line = parser->line;
 235         parser->cur_chunk.s = s;
 236         parser->cur_chunk.e = e;
 237 }
 238
 239 static const char *
 240 template_format_chunk(struct template_parser *parser, size_t *sz)
 241 {
 242         const char *s, *p;
 243         const char *head, *tail;
 244         struct template_chunk *c = &parser->prv_chunk;
 245         struct template_buffer *buf;
 246
 247         *sz = 0;
 248         s = parser->gc = NULL;
 249
 250         if (parser->strip_before && c->type == T_TYPE_TEXT)
 251         {
 252                 while ((c->e > c->s) && isspace(*(c->e - 1)))
 253                         c->e--;
 254         }
 255
 256         /* empty chunk */
 257         if (c->s == c->e)
 258         {
 259                 if (c->type == T_TYPE_EOF)
 260                 {
 261                         *sz = 0;
 262                         s = NULL;
 263                 }
 264                 else
 265                 {
 266                         *sz = 1;
 267                         s = " ";
 268                 }
 269         }
 270
 271         /* format chunk */
 272         else if ((buf = buf_init(c->e - c->s)) != NULL)
 273         {
 274                 if ((head = gen_code[c->type][0]) != NULL)
 275                         buf_append(buf, head, strlen(head));
 276
 277                 switch (c->type)
 278                 {
 279                         case T_TYPE_TEXT:
 280                                 luastr_escape(buf, c->s, c->e - c->s, 0);
 281                                 break;
 282
 283                         case T_TYPE_EXPR:
 284                                 buf_append(buf, c->s, c->e - c->s);
 285                                 for (p = c->s; p < c->e; p++)
 286                                         parser->line += (*p == '\n');
 287                                 break;
 288
 289                         case T_TYPE_INCLUDE:
 290                                 luastr_escape(buf, c->s, c->e - c->s, 0);
 291                                 break;
 292
 293                         case T_TYPE_I18N:
 294                                 luastr_translate(buf, c->s, c->e - c->s, 1);
 295                                 break;
 296
 297                         case T_TYPE_I18N_RAW:
 298                                 luastr_translate(buf, c->s, c->e - c->s, 0);
 299                                 break;
 300
 301                         case T_TYPE_CODE:
 302                                 buf_append(buf, c->s, c->e - c->s);
 303                                 for (p = c->s; p < c->e; p++)
 304                                         parser->line += (*p == '\n');
 305                                 break;
 306                 }
 307
 308                 if ((tail = gen_code[c->type][1]) != NULL)
 309                         buf_append(buf, tail, strlen(tail));
 310
 311                 *sz = buf_length(buf);
 312                 s = parser->gc = buf_destroy(buf);
 313
 314                 if (!*sz)
 315                 {
 316                         *sz = 1;
 317                         s = " ";
 318                 }
 319         }
 320
 321         return s;
 322 }
 323
 324 const char *template_reader(lua_State *L, void *ud, size_t *sz)
 325 {
 326         struct template_parser *parser = ud;
 327         int rem = parser->size - (parser->off - parser->data);
 328         char *tag;
 329
 330         parser->prv_chunk = parser->cur_chunk;
 331
 332         /* free previous string */
 333         if (parser->gc)
 334         {
 335                 free(parser->gc);
 336                 parser->gc = NULL;
 337         }
 338
 339         /* before tag */
 340         if (!parser->in_expr)
 341         {
 342                 if ((tag = strfind(parser->off, rem, "<%", 2)) != NULL)
 343                 {
 344                         template_text(parser, tag);
 345                         parser->off = tag + 2;
 346                         parser->in_expr = 1;
 347                 }
 348                 else
 349                 {
 350                         template_text(parser, parser->data + parser->size);
 351                         parser->off = parser->data + parser->size;
 352                 }
 353         }
 354
 355         /* inside tag */
 356         else
 357         {
 358                 if ((tag = strfind(parser->off, rem, "%>", 2)) != NULL)
 359                 {
 360                         template_code(parser, tag);
 361                         parser->off = tag + 2;
 362                         parser->in_expr = 0;
 363                 }
 364                 else
 365                 {
 366                         /* unexpected EOF */
 367                         template_code(parser, parser->data + parser->size);
 368
 369                         *sz = 1;
 370                         return "\033";
 371                 }
 372         }
 373
 374         return template_format_chunk(parser, sz);
 375 }
 376
 377 int template_error(lua_State *L, struct template_parser *parser)
 378 {
 379         const char *err = luaL_checkstring(L, -1);
 380         const char *off = parser->prv_chunk.s;
 381         const char *ptr;
 382         char msg[1024];
 383         int line = 0;
 384         int chunkline = 0;
 385
 386         if ((ptr = strfind((char *)err, strlen(err), "]:", 2)) != NULL)
 387         {
 388                 chunkline = atoi(ptr + 2) - parser->prv_chunk.line;
 389
 390                 while (*ptr)
 391                 {
 392                         if (*ptr++ == ' ')
 393                         {
 394                                 err = ptr;
 395                                 break;
 396                         }
 397                 }
 398         }
 399
 400         if (strfind((char *)err, strlen(err), "'char(27)'", 10) != NULL)
 401         {
 402                 off = parser->data + parser->size;
 403                 err = "'%>' expected before end of file";
 404                 chunkline = 0;
 405         }
 406
 407         for (ptr = parser->data; ptr < off; ptr++)
 408                 if (*ptr == '\n')
 409                         line++;
 410
 411         snprintf(msg, sizeof(msg), "Syntax error in %s:%d: %s",
 412                          parser->file ? parser->file : "[string]", line + chunkline, err ? err : "(unknown error)");
 413
 414         lua_pushnil(L);
 415         lua_pushinteger(L, line + chunkline);
 416         lua_pushstring(L, msg);
 417
 418         return 3;
 419 }