diplodocus.org Git - nmh/blob - sbr/icalparse.y

   1 /* icalparse.y -- icalendar (RFC 5545) parser
   2  *
   3  * This code is Copyright (c) 2014, by the authors of nmh.  See the
   4  * COPYRIGHT file in the root directory of the nmh distribution for
   5  * complete copyright information.
   6  */
   7
   8 %{
   9     /*
  10      * Use these yy* #defines, instead of the -p command line
  11      * option, to allow multiple parsers in a program.  yyval
  12      * is generated by Solaris yacc and is of type YYSTYPE.
  13      * All other yy* symbols are data of a built-in type and
  14      * are initialized by yyparse(), so they can be shared
  15      * between different parsers.
  16      */
  17 #define yydebug icaldebug
  18 #define yyerror icalerror
  19 #define yylex   icallex
  20 #define yylval  icallval
  21 #define yyval   icalval
  22 #define yyparse icalparse
  23 #define YYDEBUG 1
  24 #define YYERROR_DEBUG
  25 #define YYERROR_VERBOSE
  26 #define YY_NO_LEAKS
  27
  28     /*
  29      * To quiet compile warnings with Solaris yacc:
  30 #ifdef sun
  31 # define lint 1
  32 # undef YYDEBUG
  33 #endif
  34     */
  35
  36 #include "h/mh.h"
  37 #include "error.h"
  38 #include "h/icalendar.h"
  39 #include "h/utils.h"
  40
  41 static char *append (contentline *, const char *, const size_t);
  42 static void new_content_line (contentline **);
  43 static void new_vevent (vevent *);
  44 static void free_param_names (param_list *);
  45 static void free_param_values (value_list *);
  46 static int icalerror (const char *);
  47 %}
  48
  49 %token ICAL_NAME ICAL_COLON ICAL_VALUE ICAL_CRLF ICAL_SEMICOLON
  50 %token ICAL_PARAM_NAME ICAL_EQUAL ICAL_PARAM_VALUE ICAL_COMMA
  51
  52 %start contentline_list
  53
  54 %%
  55
  56     /* Instead of rigorous definition, cheat based on fact that every
  57        icalbody line looks like a contentline.  And we don't need to
  58        parse values. */
  59 contentline_list
  60     : contentline
  61     | contentline_list contentline
  62
  63     /* contentline = name *(";" param ) ":" value CRLF */
  64 contentline
  65     : ICAL_NAME {
  66           new_content_line (&vevents.last->contentlines);
  67           append (vevents.last->contentlines->last, $1, strlen ($1));
  68           vevents.last->contentlines->last->name = $1;
  69       } ICAL_COLON {
  70           append (vevents.last->contentlines->last, $3, strlen ($3));
  71       } ICAL_VALUE {
  72           append (vevents.last->contentlines->last, $5, strlen ($5));
  73           vevents.last->contentlines->last->value = $5;
  74       } ICAL_CRLF {
  75           append (vevents.last->contentlines->last, $7, strlen ($7));
  76           if (vevents.last->contentlines->cr_before_lf == CR_UNSET) {
  77               vevents.last->contentlines->cr_before_lf =
  78                   $7[0] == '\r'  ?  CR_BEFORE_LF  :  LF_ONLY;
  79           }
  80           /* END:VEVENT doesn't have a param_list so we don't need
  81              to check for it below. */
  82           if (vevents.last->contentlines->last->name  &&
  83               vevents.last->contentlines->last->value  &&
  84               ! strcasecmp (vevents.last->contentlines->last->name, "END")  &&
  85               ! strcasecmp (vevents.last->contentlines->last->value,
  86                             "VEVENT")) {
  87               new_vevent (&vevents);
  88           }
  89       }
  90     | ICAL_NAME {
  91           new_content_line (&vevents.last->contentlines);
  92           append (vevents.last->contentlines->last, $1, strlen ($1));
  93           vevents.last->contentlines->last->name = $1;
  94       } param_list ICAL_COLON {
  95           append (vevents.last->contentlines->last, $4, strlen ($4));
  96       } ICAL_VALUE {
  97           append (vevents.last->contentlines->last, $6, strlen ($6));
  98           vevents.last->contentlines->last->value = $6;
  99       } ICAL_CRLF {
 100           append (vevents.last->contentlines->last, $8, strlen ($8));
 101           if (vevents.last->contentlines->cr_before_lf == CR_UNSET) {
 102               vevents.last->contentlines->cr_before_lf =
 103                   $8[0] == '\r'  ?  CR_BEFORE_LF  :  LF_ONLY;
 104           }
 105       }
 106
 107 param_list
 108     : ICAL_SEMICOLON {
 109           append (vevents.last->contentlines->last, $1, strlen ($1));
 110       } param
 111     | param_list ICAL_SEMICOLON {
 112           append (vevents.last->contentlines->last, $2, strlen ($2));
 113       } param
 114
 115     /* param = param-name "=" param-value *("," param-value) */
 116 param
 117     : ICAL_PARAM_NAME {
 118           append (vevents.last->contentlines->last, $1, strlen ($1));
 119           add_param_name (vevents.last->contentlines->last, $1);
 120       } ICAL_EQUAL {
 121           append (vevents.last->contentlines->last, $3, strlen ($3));
 122       } param_value_list
 123
 124 param_value_list
 125     : ICAL_PARAM_VALUE {
 126           append (vevents.last->contentlines->last, $1, strlen ($1));
 127           add_param_value (vevents.last->contentlines->last, $1);
 128       }
 129     | param_value_list ICAL_COMMA {
 130           append (vevents.last->contentlines->last, $2, strlen ($2));
 131       } ICAL_PARAM_VALUE {
 132           append (vevents.last->contentlines->last, $4, strlen ($4));
 133           add_param_value (vevents.last->contentlines->last, $4);
 134       }
 135
 136 %%
 137
 138 /*
 139  * Remove the contentline node (by setting its name to NULL).
 140  */
 141 void
 142 remove_contentline (contentline *node)
 143 {
 144     free (node->name);
 145     node->name = NULL;
 146 }
 147
 148 contentline *
 149 add_contentline (contentline *node, const char *name)
 150 {
 151     contentline *new_node;
 152
 153     NEW0(new_node);
 154     new_node->name  = mh_xstrdup (name);
 155     new_node->next = node->next;
 156     node->next = new_node;
 157
 158     return new_node;
 159 }
 160
 161 /*
 162  * Remove the value from a value_list.
 163  */
 164 void
 165 remove_value (value_list *node)
 166 {
 167     free (node->value);
 168     node->value = NULL;
 169 }
 170
 171 /*
 172  * Find the contentline with the specified name, and optionally,
 173  * the specified value and/or parameter name.
 174  */
 175 contentline *
 176 find_contentline (contentline *contentlines, const char *name,
 177                   const char *val)
 178 {
 179     contentline *node;
 180
 181     for (node = contentlines; node; node = node->next) {
 182         /* node->name will be NULL if the line was "deleted". */
 183         if (node->name  &&  ! strcasecmp (name, node->name)) {
 184             if (!val || !node->value || !strcasecmp(val, node->value))
 185                 return node;
 186         }
 187     }
 188
 189     return NULL;
 190 }
 191
 192 static char *
 193 append (contentline *cline, const char *src, const size_t src_len)
 194 {
 195     if (src_len > 0) {
 196         const size_t len = cline->input_line_len + src_len;
 197
 198         while (len >= cline->input_line_size) {
 199             cline->input_line_size = cline->input_line_size == 0
 200                 ?  NMH_BUFSIZ
 201                 :  2 * cline->input_line_size;
 202             cline->input_line =
 203                 mh_xrealloc (cline->input_line, cline->input_line_size);
 204         }
 205
 206         memcpy (cline->input_line + cline->input_line_len, src, src_len);
 207         cline->input_line[len] = '\0';
 208         cline->input_line_len = len;
 209     }
 210
 211     return cline->input_line;
 212 }
 213
 214 static void
 215 new_content_line (contentline **cline)
 216 {
 217     contentline *new_node;
 218
 219     NEW0(new_node);
 220     if (*cline) {
 221         /* Append the new node to the end of the list. */
 222         (*cline)->last->next = new_node;
 223     } else {
 224         /* First line:  save the root node in *cline. */
 225         *cline = new_node;
 226     }
 227
 228     /* Only maintain the pointer to the last node in the root node. */
 229     (*cline)->last = new_node;
 230 }
 231
 232 static void
 233 new_vevent (vevent *event)
 234 {
 235     vevent *new_node, *node;
 236
 237     NEW0(new_node);
 238
 239     /* Append the new node to the end of the list. */
 240     for (node = event; node->next; node = node->next) { continue; }
 241     event->last =  node->next = new_node;
 242 }
 243
 244 void
 245 add_param_name (contentline *cline, char *name)
 246 {
 247     param_list *new_node;
 248     param_list *p;
 249
 250     NEW0(new_node);
 251     new_node->param_name = name;
 252
 253     if (cline->params) {
 254         for (p = cline->params; p->next; p = p->next) { continue; }
 255         /* The loop terminated at, not after, the last node. */
 256         p->next = new_node;
 257     } else {
 258         cline->params = new_node;
 259     }
 260 }
 261
 262 /*
 263  * Add a value to the last parameter seen.
 264  */
 265 void
 266 add_param_value (contentline *cline, char *value)
 267 {
 268     value_list *new_node;
 269     param_list *p;
 270     value_list *v;
 271
 272     NEW0(new_node);
 273     new_node->value = value;
 274
 275     if (cline->params) {
 276         for (p = cline->params; p->next; p = p->next) { continue; }
 277         /* The loop terminated at, not after, the last param_list node. */
 278
 279         if (p->values) {
 280             for (v = p->values; v->next; v = v->next) { continue; }
 281             /* The loop terminated at, not after, the last value_list node. */
 282             v->next = new_node;
 283         } else {
 284             p->values = new_node;
 285         }
 286     } else {
 287         /* Never should get here because a param value is always
 288            preceded by a param name. */
 289         free (new_node);
 290     }
 291 }
 292
 293 void
 294 free_contentlines (contentline *root)
 295 {
 296     contentline *i, *next;
 297
 298     for (i = root; i; i = next) {
 299         free (i->name);
 300         if (i->params) {
 301             free_param_names (i->params);
 302         }
 303         free (i->value);
 304         free (i->input_line);
 305         charstring_free (i->unexpected);
 306         next = i->next;
 307         free (i);
 308     }
 309 }
 310
 311 static void
 312 free_param_names (param_list *p)
 313 {
 314     param_list *next;
 315
 316     for ( ; p; p = next) {
 317         free (p->param_name);
 318         free_param_values (p->values);
 319         next = p->next;
 320         free (p);
 321     }
 322 }
 323
 324 static void
 325 free_param_values (value_list *v)
 326 {
 327     value_list *next;
 328
 329     for ( ; v; v = next) {
 330         free (v->value);
 331         next = v->next;
 332         free (v);
 333     }
 334 }
 335
 336 static int
 337 icalerror (const char *error)
 338 {
 339     contentline *c;
 340     charstring_t context = NULL;
 341
 342     /* Find last chunk of unexpected text. */
 343     for (c = vevents.last->contentlines; c; c = c->next) {
 344         if (c->unexpected) {
 345             context = c->unexpected;
 346         }
 347     }
 348
 349     if (! strcmp ("syntax error, unexpected $end, expecting ICAL_NAME",
 350                   error)) {
 351         /* Empty input: produce no output. */
 352     } else {
 353         if (context) {
 354             inform ("%s after \"%s\"", error, charstring_buffer (context));
 355         } else {
 356             inform ("%s", error);
 357         }
 358         parser_status = -1;
 359         return -1;
 360     }
 361
 362     return 0;  /* The return value isn't used anyway. */
 363 }
 364
 365 /*
 366  * In case YYDEBUG is disabled above; mhical refers to icaldebug.
 367  */
 368 #if ! defined YYDEBUG  ||  ! YYDEBUG
 369 int icaldebug;
 370 #endif /* ! YYDEBUG */