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

   1 /*
   2  * icalparse.y -- icalendar (RFC 5545) parser
   3  *
   4  * This code is Copyright (c) 2014, by the authors of nmh.  See the
   5  * COPYRIGHT file in the root directory of the nmh distribution for
   6  * complete copyright information.
   7  */
   8
   9 %{
  10     /*
  11      * Use these yy* #defines, instead of the -p command line
  12      * option, to allow multiple parsers in a program.  yyval
  13      * is generated by Solaris yacc and is of type YYSTYPE.
  14      * All other yy* symbols are data of a built-in type and
  15      * are initialized by yyparse(), so they can be shared
  16      * between different parsers.
  17      */
  18 #define yydebug icaldebug
  19 #define yyerror icalerror
  20 #define yylex   icallex
  21 #define yylval  icallval
  22 #define yyval   icalval
  23 #define yyparse icalparse
  24 #define YYDEBUG 1
  25 #define YYERROR_DEBUG
  26 #define YYERROR_VERBOSE
  27 #define YY_NO_LEAKS
  28
  29     /*
  30      * To quiet compile warnings with Solaris yacc:
  31 #ifdef sun
  32 # define lint 1
  33 # undef YYDEBUG
  34 #endif
  35     */
  36
  37 #include "h/mh.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_input_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_input_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_input_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     free (node->name);
 144     node->name = NULL;
 145 }
 146
 147 contentline *
 148 add_contentline (contentline *node, const char *name) {
 149     contentline *new_node;
 150
 151     NEW0(new_node);
 152     new_node->name  = strdup (name);
 153     new_node->next = node->next;
 154     node->next = new_node;
 155
 156     return new_node;
 157 }
 158
 159 /*
 160  * Remove the value from a value_list.
 161  */
 162 void
 163 remove_value (value_list *node) {
 164     free (node->value);
 165     node->value = NULL;
 166 }
 167
 168 /*
 169  * Find the contentline with the specified name, and optionally,
 170  * the specified value and/or parameter name.
 171  */
 172 contentline *
 173 find_contentline (contentline *contentlines, const char *name,
 174                   const char *val) {
 175     contentline *node;
 176
 177     for (node = contentlines; node; node = node->next) {
 178         /* node->name will be NULL if the line was "deleted". */
 179         if (node->name  &&  ! strcasecmp (name, node->name)) {
 180             if (val  &&  node->value) {
 181                 if (! strcasecmp (val, node->value)) {
 182                     return node;
 183                 }
 184             } else {
 185                 return node;
 186             }
 187         }
 188     }
 189
 190     return NULL;
 191 }
 192
 193 static char *
 194 append (contentline *cline, const char *src, const size_t src_len) {
 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                 ?  (BUFSIZ>=8192 ? BUFSIZ : 8192)
 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_input_line (contentline **cline) {
 216     contentline *new_node;
 217
 218     NEW0(new_node);
 219     if (*cline) {
 220         /* Append the new node to the end of the list. */
 221         (*cline)->last->next = new_node;
 222     } else {
 223         /* First line:  save the root node in *cline. */
 224         *cline = new_node;
 225     }
 226
 227     /* Only maintain the pointer to the last node in the root node. */
 228     (*cline)->last = new_node;
 229 }
 230
 231 static void
 232 new_vevent (vevent *event) {
 233     vevent *new_node, *node;
 234
 235     NEW0(new_node);
 236
 237     /* Append the new node to the end of the list. */
 238     for (node = event; node->next; node = node->next) { continue; }
 239     event->last =  node->next = new_node;
 240 }
 241
 242 void
 243 add_param_name (contentline *cline, char *name) {
 244     param_list *new_node;
 245     param_list *p;
 246
 247     NEW0(new_node);
 248     new_node->param_name = name;
 249
 250     if (cline->params) {
 251         for (p = cline->params; p->next; p = p->next) { continue; }
 252         /* The loop terminated at, not after, the last node. */
 253         p->next = new_node;
 254     } else {
 255         cline->params = new_node;
 256     }
 257 }
 258
 259 /*
 260  * Add a value to the last parameter seen.
 261  */
 262 void
 263 add_param_value (contentline *cline, char *value) {
 264     value_list *new_node;
 265     param_list *p;
 266     value_list *v;
 267
 268     NEW0(new_node);
 269     new_node->value = value;
 270
 271     if (cline->params) {
 272         for (p = cline->params; p->next; p = p->next) { continue; }
 273         /* The loop terminated at, not after, the last param_list node. */
 274
 275         if (p->values) {
 276             for (v = p->values; v->next; v = v->next) { continue; }
 277             /* The loop terminated at, not after, the last value_list node. */
 278             v->next = new_node;
 279         } else {
 280             p->values = new_node;
 281         }
 282     } else {
 283         /* Never should get here because a param value is always
 284            preceded by a param name. */
 285         free (new_node);
 286     }
 287 }
 288
 289 void
 290 free_contentlines (contentline *root) {
 291     contentline *i, *next;
 292
 293     for (i = root; i; i = next) {
 294         free (i->name);
 295         if (i->params) {
 296             free_param_names (i->params);
 297         }
 298         free (i->value);
 299         free (i->input_line);
 300         next = i->next;
 301         free (i);
 302     }
 303 }
 304
 305 static void
 306 free_param_names (param_list *p) {
 307     param_list *next;
 308
 309     for ( ; p; p = next) {
 310         free (p->param_name);
 311         free_param_values (p->values);
 312         next = p->next;
 313         free (p);
 314     }
 315 }
 316
 317 static void
 318 free_param_values (value_list *v) {
 319     value_list *next;
 320
 321     for ( ; v; v = next) {
 322         free (v->value);
 323         next = v->next;
 324         free (v);
 325     }
 326 }
 327
 328 static int
 329 icalerror (const char *error) {
 330     if (! strcmp ("syntax error, unexpected $end, expecting ICAL_NAME",
 331                   error)) {
 332         /* Empty input: produce no output. */
 333     } else {
 334         adios (NULL, "%s", error);
 335     }
 336
 337     return 0;  /* The return value isn't used anyway. */
 338 }
 339
 340 /*
 341  * In case YYDEBUG is disabled above; mhical refers to icaldebug.
 342  */
 343 #if ! defined YYDEBUG  ||  ! YYDEBUG
 344 int icaldebug;
 345 #endif /* ! YYDEBUG */