libs/web/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         static 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->mmap = mmap(NULL, parser->size, PROT_READ, MAP_PRIVATE,
  86                                                 parser->fd, 0);
  87
  88         if (parser->mmap != MAP_FAILED)
  89         {
  90                 parser->off = parser->mmap;
  91                 parser->cur_chunk.type = T_TYPE_INIT;
  92                 parser->cur_chunk.s    = parser->mmap;
  93                 parser->cur_chunk.e    = parser->mmap;
  94
  95                 return parser;
  96         }
  97
  98 err:
  99         template_close(parser);
 100         return NULL;
 101 }
 102
 103 void template_close(struct template_parser *parser)
 104 {
 105         if (!parser)
 106                 return;
 107
 108         if (parser->gc != NULL)
 109                 free(parser->gc);
 110
 111         if ((parser->mmap != NULL) && (parser->mmap != MAP_FAILED))
 112                 munmap(parser->mmap, parser->size);
 113
 114         if (parser->fd >= 0)
 115                 close(parser->fd);
 116
 117         free(parser);
 118 }
 119
 120 void template_text(struct template_parser *parser, const char *e)
 121 {
 122         const char *s = parser->off;
 123
 124         if (s < (parser->mmap + parser->size))
 125         {
 126                 if (parser->strip_after)
 127                 {
 128                         while ((s <= e) && isspace(*s))
 129                                 s++;
 130                 }
 131
 132                 parser->cur_chunk.type = T_TYPE_TEXT;
 133         }
 134         else
 135         {
 136                 parser->cur_chunk.type = T_TYPE_EOF;
 137         }
 138
 139         parser->cur_chunk.line = parser->line;
 140         parser->cur_chunk.s = s;
 141         parser->cur_chunk.e = e;
 142 }
 143
 144 void template_code(struct template_parser *parser, const char *e)
 145 {
 146         const char *s = parser->off;
 147
 148         parser->strip_before = 0;
 149         parser->strip_after = 0;
 150
 151         if (*s == '-')
 152         {
 153                 parser->strip_before = 1;
 154                 for (s++; (s <= e) && (*s == ' ' || *s == '\t'); s++);
 155         }
 156
 157         if (*(e-1) == '-')
 158         {
 159                 parser->strip_after = 1;
 160                 for (e--; (e >= s) && (*e == ' ' || *e == '\t'); e--);
 161         }
 162
 163         switch (*s)
 164         {
 165                 /* comment */
 166                 case '#':
 167                         s++;
 168                         parser->cur_chunk.type = T_TYPE_COMMENT;
 169                         break;
 170
 171                 /* include */
 172                 case '+':
 173                         s++;
 174                         parser->cur_chunk.type = T_TYPE_INCLUDE;
 175                         break;
 176
 177                 /* translate */
 178                 case ':':
 179                         s++;
 180                         parser->cur_chunk.type = T_TYPE_I18N;
 181                         break;
 182
 183                 /* translate raw */
 184                 case '_':
 185                         s++;
 186                         parser->cur_chunk.type = T_TYPE_I18N_RAW;
 187                         break;
 188
 189                 /* expr */
 190                 case '=':
 191                         s++;
 192                         parser->cur_chunk.type = T_TYPE_EXPR;
 193                         break;
 194
 195                 /* code */
 196                 default:
 197                         parser->cur_chunk.type = T_TYPE_CODE;
 198                         break;
 199         }
 200
 201         parser->cur_chunk.line = parser->line;
 202         parser->cur_chunk.s = s;
 203         parser->cur_chunk.e = e;
 204 }
 205
 206 static const char *
 207 template_format_chunk(struct template_parser *parser, size_t *sz)
 208 {
 209         const char *s, *p;
 210         const char *head, *tail;
 211         struct template_chunk *c = &parser->prv_chunk;
 212         struct template_buffer *buf;
 213
 214         *sz = 0;
 215         s = parser->gc = NULL;
 216
 217         if (parser->strip_before && c->type == T_TYPE_TEXT)
 218         {
 219                 while ((c->e > c->s) && isspace(*(c->e - 1)))
 220                         c->e--;
 221         }
 222
 223         /* empty chunk */
 224         if (c->s == c->e)
 225         {
 226                 if (c->type == T_TYPE_EOF)
 227                 {
 228                         *sz = 0;
 229                         s = NULL;
 230                 }
 231                 else
 232                 {
 233                         *sz = 1;
 234                         s = " ";
 235                 }
 236         }
 237
 238         /* format chunk */
 239         else if ((buf = buf_init(c->e - c->s)) != NULL)
 240         {
 241                 if ((head = gen_code[c->type][0]) != NULL)
 242                         buf_append(buf, head, strlen(head));
 243
 244                 switch (c->type)
 245                 {
 246                         case T_TYPE_TEXT:
 247                                 luastr_escape(buf, c->s, c->e - c->s, 0);
 248                                 break;
 249
 250                         case T_TYPE_EXPR:
 251                                 buf_append(buf, c->s, c->e - c->s);
 252                                 for (p = c->s; p < c->e; p++)
 253                                         parser->line += (*p == '\n');
 254                                 break;
 255
 256                         case T_TYPE_INCLUDE:
 257                                 luastr_escape(buf, c->s, c->e - c->s, 0);
 258                                 break;
 259
 260                         case T_TYPE_I18N:
 261                                 luastr_translate(buf, c->s, c->e - c->s, 1);
 262                                 break;
 263
 264                         case T_TYPE_I18N_RAW:
 265                                 luastr_translate(buf, c->s, c->e - c->s, 0);
 266                                 break;
 267
 268                         case T_TYPE_CODE:
 269                                 buf_append(buf, c->s, c->e - c->s);
 270                                 for (p = c->s; p < c->e; p++)
 271                                         parser->line += (*p == '\n');
 272                                 break;
 273                 }
 274
 275                 if ((tail = gen_code[c->type][1]) != NULL)
 276                         buf_append(buf, tail, strlen(tail));
 277
 278                 *sz = buf_length(buf);
 279                 s = parser->gc = buf_destroy(buf);
 280
 281                 if (!*sz)
 282                 {
 283                         *sz = 1;
 284                         s = " ";
 285                 }
 286         }
 287
 288         return s;
 289 }
 290
 291 const char *template_reader(lua_State *L, void *ud, size_t *sz)
 292 {
 293         struct template_parser *parser = ud;
 294         int rem = parser->size - (parser->off - parser->mmap);
 295         char *tag;
 296
 297         parser->prv_chunk = parser->cur_chunk;
 298
 299         /* free previous string */
 300         if (parser->gc)
 301         {
 302                 free(parser->gc);
 303                 parser->gc = NULL;
 304         }
 305
 306         /* before tag */
 307         if (!parser->in_expr)
 308         {
 309                 if ((tag = strfind(parser->off, rem, "<%", 2)) != NULL)
 310                 {
 311                         template_text(parser, tag);
 312                         parser->off = tag + 2;
 313                         parser->in_expr = 1;
 314                 }
 315                 else
 316                 {
 317                         template_text(parser, parser->mmap + parser->size);
 318                         parser->off = parser->mmap + parser->size;
 319                 }
 320         }
 321
 322         /* inside tag */
 323         else
 324         {
 325                 if ((tag = strfind(parser->off, rem, "%>", 2)) != NULL)
 326                 {
 327                         template_code(parser, tag);
 328                         parser->off = tag + 2;
 329                         parser->in_expr = 0;
 330                 }
 331                 else
 332                 {
 333                         /* unexpected EOF */
 334                         template_code(parser, parser->mmap + parser->size);
 335
 336                         *sz = 1;
 337                         return "\033";
 338                 }
 339         }
 340
 341         return template_format_chunk(parser, sz);
 342 }
 343
 344 int template_error(lua_State *L, struct template_parser *parser)
 345 {
 346         const char *err = luaL_checkstring(L, -1);
 347         const char *off = parser->prv_chunk.s;
 348         const char *ptr;
 349         char msg[1024];
 350         int line = 0;
 351         int chunkline = 0;
 352
 353         if ((ptr = strfind((char *)err, strlen(err), "]:", 2)) != NULL)
 354         {
 355                 chunkline = atoi(ptr + 2) - parser->prv_chunk.line;
 356
 357                 while (*ptr)
 358                 {
 359                         if (*ptr++ == ' ')
 360                         {
 361                                 err = ptr;
 362                                 break;
 363                         }
 364                 }
 365         }
 366
 367         if (strfind((char *)err, strlen(err), "'char(27)'", 10) != NULL)
 368         {
 369                 off = parser->mmap + parser->size;
 370                 err = "'%>' expected before end of file";
 371                 chunkline = 0;
 372         }
 373
 374         for (ptr = parser->mmap; ptr < off; ptr++)
 375                 if (*ptr == '\n')
 376                         line++;
 377
 378         snprintf(msg, sizeof(msg), "Syntax error in %s:%d: %s",
 379                          parser->file, line + chunkline, err ? err : "(unknown error)");
 380
 381         lua_pushnil(L);
 382         lua_pushinteger(L, line + chunkline);
 383         lua_pushstring(L, msg);
 384
 385         return 3;
 386 }