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 "h/icalendar.h"
  38 #include "h/utils.h"
  39
  40 static char *append (contentline *, const char *, const size_t);
  41 static void new_content_line (contentline **);
  42 static void new_vevent (vevent *);
  43 static void free_param_names (param_list *);
  44 static void free_param_values (value_list *);
  45 static int icalerror (const char *);
  46 %}
  47
  48 %token ICAL_NAME ICAL_COLON ICAL_VALUE ICAL_CRLF ICAL_SEMICOLON
  49 %token ICAL_PARAM_NAME ICAL_EQUAL ICAL_PARAM_VALUE ICAL_COMMA
  50
  51 %start contentline_list
  52
  53 %%
  54
  55     /* Instead of rigorous definition, cheat based on fact that every
  56        icalbody line looks like a contentline.  And we don't need to
  57        parse values. */
  58 contentline_list
  59     : contentline
  60     | contentline_list contentline
  61
  62     /* contentline = name *(";" param ) ":" value CRLF */
  63 contentline
  64     : ICAL_NAME {
  65           new_content_line (&vevents.last->contentlines);
  66           append (vevents.last->contentlines->last, $1, strlen ($1));
  67           vevents.last->contentlines->last->name = $1;
  68       } ICAL_COLON {
  69           append (vevents.last->contentlines->last, $3, strlen ($3));
  70       } ICAL_VALUE {
  71           append (vevents.last->contentlines->last, $5, strlen ($5));
  72           vevents.last->contentlines->last->value = $5;
  73       } ICAL_CRLF {
  74           append (vevents.last->contentlines->last, $7, strlen ($7));
  75           if (vevents.last->contentlines->cr_before_lf == CR_UNSET) {
  76               vevents.last->contentlines->cr_before_lf =
  77                   $7[0] == '\r'  ?  CR_BEFORE_LF  :  LF_ONLY;
  78           }
  79           /* END:VEVENT doesn't have a param_list so we don't need
  80              to check for it below. */
  81           if (vevents.last->contentlines->last->name  &&
  82               vevents.last->contentlines->last->value  &&
  83               ! strcasecmp (vevents.last->contentlines->last->name, "END")  &&
  84               ! strcasecmp (vevents.last->contentlines->last->value,
  85                             "VEVENT")) {
  86               new_vevent (&vevents);
  87           }
  88       }
  89     | ICAL_NAME {
  90           new_content_line (&vevents.last->contentlines);
  91           append (vevents.last->contentlines->last, $1, strlen ($1));
  92           vevents.last->contentlines->last->name = $1;
  93       } param_list ICAL_COLON {
  94           append (vevents.last->contentlines->last, $4, strlen ($4));
  95       } ICAL_VALUE {
  96           append (vevents.last->contentlines->last, $6, strlen ($6));
  97           vevents.last->contentlines->last->value = $6;
  98       } ICAL_CRLF {
  99           append (vevents.last->contentlines->last, $8, strlen ($8));
 100           if (vevents.last->contentlines->cr_before_lf == CR_UNSET) {
 101               vevents.last->contentlines->cr_before_lf =
 102                   $8[0] == '\r'  ?  CR_BEFORE_LF  :  LF_ONLY;
 103           }
 104       }
 105
 106 param_list
 107     : ICAL_SEMICOLON {
 108           append (vevents.last->contentlines->last, $1, strlen ($1));
 109       } param
 110     | param_list ICAL_SEMICOLON {
 111           append (vevents.last->contentlines->last, $2, strlen ($2));
 112       } param
 113
 114     /* param = param-name "=" param-value *("," param-value) */
 115 param
 116     : ICAL_PARAM_NAME {
 117           append (vevents.last->contentlines->last, $1, strlen ($1));
 118           add_param_name (vevents.last->contentlines->last, $1);
 119       } ICAL_EQUAL {
 120           append (vevents.last->contentlines->last, $3, strlen ($3));
 121       } param_value_list
 122
 123 param_value_list
 124     : ICAL_PARAM_VALUE {
 125           append (vevents.last->contentlines->last, $1, strlen ($1));
 126           add_param_value (vevents.last->contentlines->last, $1);
 127       }
 128     | param_value_list ICAL_COMMA {
 129           append (vevents.last->contentlines->last, $2, strlen ($2));
 130       } ICAL_PARAM_VALUE {
 131           append (vevents.last->contentlines->last, $4, strlen ($4));
 132           add_param_value (vevents.last->contentlines->last, $4);
 133       }
 134
 135 %%
 136
 137 /*
 138  * Remove the contentline node (by setting its name to NULL).
 139  */
 140 void
 141 remove_contentline (contentline *node) {
 142     free (node->name);
 143     node->name = NULL;
 144 }
 145
 146 contentline *
 147 add_contentline (contentline *node, const char *name) {
 148     contentline *new_node;
 149
 150     NEW0(new_node);
 151     new_node->name  = mh_xstrdup (name);
 152     new_node->next = node->next;
 153     node->next = new_node;
 154
 155     return new_node;
 156 }
 157
 158 /*
 159  * Remove the value from a value_list.
 160  */
 161 void
 162 remove_value (value_list *node) {
 163     free (node->value);
 164     node->value = NULL;
 165 }
 166
 167 /*
 168  * Find the contentline with the specified name, and optionally,
 169  * the specified value and/or parameter name.
 170  */
 171 contentline *
 172 find_contentline (contentline *contentlines, const char *name,
 173                   const char *val) {
 174     contentline *node;
 175
 176     for (node = contentlines; node; node = node->next) {
 177         /* node->name will be NULL if the line was "deleted". */
 178         if (node->name  &&  ! strcasecmp (name, node->name)) {
 179             if (val  &&  node->value) {
 180                 if (! strcasecmp (val, node->value)) {
 181                     return node;
 182                 }
 183             } else {
 184                 return node;
 185             }
 186         }
 187     }
 188
 189     return NULL;
 190 }
 191
 192 static char *
 193 append (contentline *cline, const char *src, const size_t src_len) {
 194     if (src_len > 0) {
 195         const size_t len = cline->input_line_len + src_len;
 196
 197         while (len >= cline->input_line_size) {
 198             cline->input_line_size = cline->input_line_size == 0
 199                 ?  NMH_BUFSIZ
 200                 :  2 * cline->input_line_size;
 201             cline->input_line =
 202                 mh_xrealloc (cline->input_line, cline->input_line_size);
 203         }
 204
 205         memcpy (cline->input_line + cline->input_line_len, src, src_len);
 206         cline->input_line[len] = '\0';
 207         cline->input_line_len = len;
 208     }
 209
 210     return cline->input_line;
 211 }
 212
 213 static void
 214 new_content_line (contentline **cline) {
 215     contentline *new_node;
 216
 217     NEW0(new_node);
 218     if (*cline) {
 219         /* Append the new node to the end of the list. */
 220         (*cline)->last->next = new_node;
 221     } else {
 222         /* First line:  save the root node in *cline. */
 223         *cline = new_node;
 224     }
 225
 226     /* Only maintain the pointer to the last node in the root node. */
 227     (*cline)->last = new_node;
 228 }
 229
 230 static void
 231 new_vevent (vevent *event) {
 232     vevent *new_node, *node;
 233
 234     NEW0(new_node);
 235
 236     /* Append the new node to the end of the list. */
 237     for (node = event; node->next; node = node->next) { continue; }
 238     event->last =  node->next = new_node;
 239 }
 240
 241 void
 242 add_param_name (contentline *cline, char *name) {
 243     param_list *new_node;
 244     param_list *p;
 245
 246     NEW0(new_node);
 247     new_node->param_name = name;
 248
 249     if (cline->params) {
 250         for (p = cline->params; p->next; p = p->next) { continue; }
 251         /* The loop terminated at, not after, the last node. */
 252         p->next = new_node;
 253     } else {
 254         cline->params = new_node;
 255     }
 256 }
 257
 258 /*
 259  * Add a value to the last parameter seen.
 260  */
 261 void
 262 add_param_value (contentline *cline, char *value) {
 263     value_list *new_node;
 264     param_list *p;
 265     value_list *v;
 266
 267     NEW0(new_node);
 268     new_node->value = value;
 269
 270     if (cline->params) {
 271         for (p = cline->params; p->next; p = p->next) { continue; }
 272         /* The loop terminated at, not after, the last param_list node. */
 273
 274         if (p->values) {
 275             for (v = p->values; v->next; v = v->next) { continue; }
 276             /* The loop terminated at, not after, the last value_list node. */
 277             v->next = new_node;
 278         } else {
 279             p->values = new_node;
 280         }
 281     } else {
 282         /* Never should get here because a param value is always
 283            preceded by a param name. */
 284         free (new_node);
 285     }
 286 }
 287
 288 void
 289 free_contentlines (contentline *root) {
 290     contentline *i, *next;
 291
 292     for (i = root; i; i = next) {
 293         free (i->name);
 294         if (i->params) {
 295             free_param_names (i->params);
 296         }
 297         free (i->value);
 298         free (i->input_line);
 299         charstring_free (i->unexpected);
 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     contentline *c;
 331     charstring_t context = NULL;
 332
 333     /* Find last chunk of unexpected text. */
 334     for (c = vevents.last->contentlines; c; c = c->next) {
 335         if (c->unexpected) {
 336             context = c->unexpected;
 337         }
 338     }
 339
 340     if (! strcmp ("syntax error, unexpected $end, expecting ICAL_NAME",
 341                   error)) {
 342         /* Empty input: produce no output. */
 343     } else {
 344         if (context) {
 345             inform ("%s after \"%s\"", error, charstring_buffer (context));
 346         } else {
 347             inform ("%s", error);
 348         }
 349         parser_status = -1;
 350         return -1;
 351     }
 352
 353     return 0;  /* The return value isn't used anyway. */
 354 }
 355
 356 /*
 357  * In case YYDEBUG is disabled above; mhical refers to icaldebug.
 358  */
 359 #if ! defined YYDEBUG  ||  ! YYDEBUG
 360 int icaldebug;
 361 #endif /* ! YYDEBUG */