src/l2l_scanner.l

   1 /*
   2  * lm2latex - src/l2l_scanner.l
   3  * Copyright (C) 2010 Sebastian Harl <sh@tokkee.org>
   4  * All rights reserved.
   5  *
   6  * Redistribution and use in source and binary forms, with or without
   7  * modification, are permitted provided that the following conditions
   8  * are met:
   9  * 1. Redistributions of source code must retain the above copyright
  10  *    notice, this list of conditions and the following disclaimer.
  11  * 2. Redistributions in binary form must reproduce the above copyright
  12  *    notice, this list of conditions and the following disclaimer in the
  13  *    documentation and/or other materials provided with the distribution.
  14  *
  15  * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  16  * ``AS IS'' AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED
  17  * TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
  18  * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT HOLDERS OR
  19  * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
  20  * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
  21  * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS;
  22  * OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY,
  23  * WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  24  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN IF
  25  * ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  26  */
  27
  28 /*
  29  * A Linux-Magazin markup to LaTeX converter -- LM markup scanner.
  30  */
  31
  32 %{
  33 #if HAVE_CONFIG_H
  34 #       include "config.h"
  35 #endif
  36
  37 #include <assert.h>
  38
  39 #include <ctype.h>
  40
  41 #include <stdarg.h>
  42 #include <stdio.h>
  43 #include <stdlib.h>
  44 #include <string.h>
  45
  46 typedef struct {
  47         char  *data;
  48         size_t size;
  49         size_t len;
  50 } l2l_strbuf_t;
  51
  52 #define L2L_STRBUF_INIT { NULL, 0, 0 }
  53 #define L2L_STRBUF_FREE(buf) ((buf)->size - (buf)->len)
  54 #define L2L_STRBUF_END(buf) ((buf)->data + (buf)->len)
  55 #define L2L_STRBUF_CLEAR(buf) ((buf)->len = 0)
  56
  57 static int
  58 l2l_strbuf_append(l2l_strbuf_t *buf, const char *fmt, ...);
  59
  60 static void
  61 l2l_strbuf_chomp(l2l_strbuf_t *buf);
  62
  63 static void
  64 l2l_strbuf_destroy(l2l_strbuf_t *buf);
  65
  66 #define L2L_YY_APPEND_OR_ECHO(strbuf, ...) \
  67         do { \
  68                 if ((strbuf)) { \
  69                         if (l2l_strbuf_append((strbuf), __VA_ARGS__)) \
  70                                 YY_FATAL_ERROR("ERROR: internal error"); \
  71                 } \
  72                 else \
  73                         fprintf(yyout, __VA_ARGS__); \
  74         } while (0)
  75
  76 #define L2L_STATE_HEADER_OR_ABORT \
  77         do { \
  78                 if (l2l_scanner_state != L2L_HEADER) \
  79                         YY_FATAL_ERROR("ERROR: unexpected header definition"); \
  80         } while (0)
  81
  82 #define L2L_PATTERN_IS(str) (! strncmp(yytext, (str), strlen(str)))
  83 #define L2L_PATTERN_IS_HEADER \
  84         (L2L_PATTERN_IS("@R:") || L2L_PATTERN_IS("@SW:") \
  85                 || L2L_PATTERN_IS("@D:") || L2L_PATTERN_IS("@T:") \
  86                 || L2L_PATTERN_IS("@A:") || L2L_PATTERN_IS("@V:"))
  87 %}
  88
  89 %option yylineno
  90 %option noyywrap
  91
  92 /* optimize for "fast scanning"; create an 8-bit scanner */
  93 %option fast 8bit
  94
  95 /* generate a reentrant scanner in its own namespace */
  96 %option reentrant
  97 %option prefix="l2l_yy" outfile="lex.yy.c"
  98
  99 %option verbose warn
 100
 101 %s box
 102
 103 %x caption box_caption
 104 %x command
 105 %x headertxt
 106 %x itemize
 107 %x listing
 108 %x title
 109 %x url
 110
 111 COMMENT @#:.*
 112 WHITESPACE [ \t]
 113
 114 ANY_COMMAND @(R|SW|D|T|V|A|L|ZT|LI|B|Bi|IT|IL|IE|KT|KL|KE|TT|TH|TL|TE):
 115
 116 %%
 117
 118 %{
 119         enum {
 120                 L2L_HEADER,
 121                 L2L_BODY,
 122                 L2L_FIGURE,
 123
 124                 L2L_UNQUOTED_TEXT,
 125                 L2L_QUOTED_TEXT,
 126         };
 127
 128         int l2l_scanner_state = L2L_HEADER;
 129         int l2l_quote_state   = L2L_UNQUOTED_TEXT;
 130
 131         /* text formatting */
 132         _Bool l2l_italic      = 0;
 133         _Bool l2l_bold        = 0;
 134         _Bool l2l_code        = 0;
 135         _Bool l2l_sup         = 0;
 136         _Bool l2l_sub         = 0;
 137         _Bool l2l_li_italic   = 0;
 138
 139         /* title page information */
 140         l2l_strbuf_t l2l_category = L2L_STRBUF_INIT;
 141         l2l_strbuf_t l2l_keyword  = L2L_STRBUF_INIT;
 142         l2l_strbuf_t l2l_title    = L2L_STRBUF_INIT;
 143         l2l_strbuf_t l2l_headline = L2L_STRBUF_INIT;
 144         l2l_strbuf_t l2l_author   = L2L_STRBUF_INIT;
 145         l2l_strbuf_t l2l_abstract = L2L_STRBUF_INIT;
 146
 147         /* temp. buffers */
 148         l2l_strbuf_t l2l_caption  = L2L_STRBUF_INIT;
 149         l2l_strbuf_t l2l_ititle   = L2L_STRBUF_INIT;
 150
 151         l2l_strbuf_t *l2l_buf_ptr = NULL;
 152
 153         int l2l_last_yystart = INITIAL;
 154 %}
 155
 156 {COMMENT} { fprintf(yyout, "%%%s", yytext + strlen("@#:")); }
 157
 158 <INITIAL,box,caption,box_caption,command,headertxt,itemize,title>{
 159         /* LaTeX reserved characters */
 160         [#$%&_{}] { L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "\\%s", yytext); }
 161         [\^~]     { L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "\\%s{}", yytext); }
 162         [\\]      { L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "$\\backslash$"); }
 163
 164         /* special characters */
 165         /* '---' and '--' are handled by LaTeX */
 166         \*\* L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "~");
 167
 168         :\* L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "\\,");
 169
 170         ["] {
 171                 if (l2l_quote_state == L2L_UNQUOTED_TEXT) {
 172                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "\"`");
 173                         l2l_quote_state = L2L_QUOTED_TEXT;
 174                 }
 175                 else {
 176                         assert(l2l_quote_state == L2L_QUOTED_TEXT);
 177                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "\"'");
 178                         l2l_quote_state = L2L_UNQUOTED_TEXT;
 179                 }
 180         }
 181
 182         /* text formatting */
 183         \<[iI]> {
 184                 if (l2l_italic) {
 185                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "}");
 186                         l2l_italic = 0;
 187                 }
 188                 else {
 189                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "{\\itshape ");
 190                         l2l_italic = 1;
 191                 }
 192         }
 193
 194         \<[bB]> {
 195                 if (l2l_bold) {
 196                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "}");
 197                         l2l_bold = 0;
 198                 }
 199                 else {
 200                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "{\\bfseries ");
 201                         l2l_bold = 1;
 202                 }
 203         }
 204
 205         \<[cC]> {
 206                 if (l2l_code) {
 207                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "}");
 208                         l2l_code = 0;
 209                 }
 210                 else {
 211                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "{\\ttfamily ");
 212                         l2l_code = 1;
 213                 }
 214         }
 215
 216         \<[\+]> {
 217                 if (l2l_sup) {
 218                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "}}");
 219                         l2l_sup = 0;
 220                 }
 221                 else {
 222                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr,
 223                                         "\\ensuremath{^{\rmfamily ");
 224                         l2l_sup = 1;
 225                 }
 226         }
 227
 228         \<[\-]> {
 229                 if (l2l_sub) {
 230                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "}}");
 231                         l2l_sub = 0;
 232                 }
 233                 else {
 234                         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr,
 235                                         "\\ensuremath{_{\rmfamily ");
 236                         l2l_sub = 1;
 237                 }
 238         }
 239 }
 240
 241 \<[uU]> {
 242         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "\\url{");
 243         BEGIN(url);
 244 }
 245
 246 <url>\<[uU]> {
 247         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "}");
 248         BEGIN(l2l_last_yystart);
 249 }
 250
 251 <url>.|\n {
 252         L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "%s", yytext);
 253 }
 254
 255         /*
 256          * header
 257          */
 258
 259 @R:{WHITESPACE}* {
 260         L2L_STATE_HEADER_OR_ABORT;
 261         l2l_buf_ptr = &l2l_category;
 262         BEGIN(headertxt);
 263 }
 264
 265 @SW:{WHITESPACE}* {
 266         L2L_STATE_HEADER_OR_ABORT;
 267         l2l_buf_ptr = &l2l_keyword;
 268         BEGIN(headertxt);
 269 }
 270
 271 @D:{WHITESPACE}* {
 272         L2L_STATE_HEADER_OR_ABORT;
 273         l2l_buf_ptr = &l2l_title;
 274         BEGIN(headertxt);
 275 }
 276
 277 @T:{WHITESPACE}* {
 278         L2L_STATE_HEADER_OR_ABORT;
 279         l2l_buf_ptr = &l2l_headline;
 280         BEGIN(headertxt);
 281 }
 282
 283 @A:{WHITESPACE}* {
 284         L2L_STATE_HEADER_OR_ABORT;
 285         l2l_buf_ptr = &l2l_author;
 286         BEGIN(headertxt);
 287 }
 288
 289 @V:{WHITESPACE}* {
 290         L2L_STATE_HEADER_OR_ABORT;
 291         l2l_buf_ptr = &l2l_abstract;
 292         BEGIN(headertxt);
 293 }
 294
 295 <headertxt>{ANY_COMMAND} {
 296         if (l2l_buf_ptr) {
 297                 l2l_strbuf_chomp(l2l_buf_ptr);
 298                 l2l_buf_ptr = NULL;
 299         }
 300
 301         if (! L2L_PATTERN_IS_HEADER) {
 302                 assert(l2l_scanner_state == L2L_HEADER);
 303
 304                 if (l2l_category.len || l2l_keyword.len
 305                                 || l2l_title.len || l2l_headline.len) {
 306                         fprintf(yyout, "\\title{");
 307
 308                         if (l2l_category.len || l2l_keyword.len) {
 309                                 fprintf(yyout, "{\\scriptsize [");
 310                                 if (l2l_category.len) {
 311                                         fprintf(yyout, "%s", l2l_category.data);
 312                                         if (l2l_keyword.len)
 313                                                 fprintf(yyout, " $\\rightarrow$ ");
 314                                 }
 315                                 if (l2l_keyword.len)
 316                                         fprintf(yyout, "%s", l2l_keyword.data);
 317                                 fprintf(yyout, "]}\\\\\n\\vspace{5mm}\n");
 318                         }
 319
 320                         if (l2l_headline.len) {
 321                                 if (l2l_title.len)
 322                                         fprintf(yyout, "\\normalsize %s\\\\\n\\LARGE ",
 323                                                         l2l_title.data);
 324                                 fprintf(yyout, "%s", l2l_headline.data);
 325                         }
 326                         else if (l2l_title.len)
 327                                 fprintf(yyout, "%s", l2l_title.data);
 328
 329                         fprintf(yyout, "}\n");
 330                 }
 331
 332                 if (l2l_author.len)
 333                         fprintf(yyout, "\\author{%s}\n", l2l_author.data);
 334                 fprintf(yyout, "\\date{\\today}\n\n");
 335
 336                 fprintf(yyout, "\\begin{document}\n\n");
 337                 l2l_scanner_state = L2L_BODY;
 338
 339                 fprintf(yyout, "\\maketitle\n\n");
 340
 341                 if (l2l_abstract.len)
 342                         fprintf(yyout, "\\begin{abstract}\n%s\n"
 343                                         "\\end{abstract}\n\n", l2l_abstract.data);
 344
 345                 fprintf(yyout, "\\twocolumn\n\n");
 346         }
 347
 348         yyless(0);
 349         BEGIN(l2l_last_yystart);
 350 }
 351
 352 <headertxt>{COMMENT} { /* ignore */ }
 353
 354 <headertxt>.|\n {
 355         if (l2l_buf_ptr)
 356                 if (l2l_strbuf_append(l2l_buf_ptr, "%s", yytext))
 357                         YY_FATAL_ERROR("ERROR: internal error");
 358         /* else ignore */
 359 }
 360
 361         /*
 362          * body
 363          */
 364
 365 \n\n{WHITESPACE}*\*{WHITESPACE}* {
 366         fprintf(yyout, "\n\n\\begin{itemize}\n\\item ");
 367         BEGIN(itemize);
 368 }
 369
 370 <itemize>({WHITESPACE}|\n)*\n\n |
 371 <itemize>({WHITESPACE}|\n)*{ANY_COMMAND} {
 372         fprintf(yyout, "\n\\end{itemize}");
 373         yyless(0);
 374         BEGIN(l2l_last_yystart);
 375 }
 376
 377         /* this will produce a longer match and, thus, take precedence over
 378          * the pattern above matching an empty line after the itemize */
 379 <itemize>({WHITESPACE}|\n)*\n{WHITESPACE}*\*{WHITESPACE}* {
 380         fprintf(yyout, "\n\\item ");
 381 }
 382 <itemize>({WHITESPACE}|\n)*\n\n({WHITESPACE}{2,}|\t) ECHO;
 383
 384 <itemize>. ECHO;
 385
 386 @ZT:{WHITESPACE}* {
 387         fprintf(yyout, "\\subsection*{");
 388         BEGIN(command);
 389 }
 390
 391 <command>({WHITESPACE}|\n)+{ANY_COMMAND} {
 392         fprintf(yyout, "}");
 393         yyless(0);
 394         BEGIN(l2l_last_yystart);
 395 }
 396
 397 <command>. ECHO;
 398
 399 @LI:{WHITESPACE}*\n? {
 400         /* \xb7 = MIDDLE DOT (iso-8859-1 and iso-8859-15) */
 401         fprintf(yyout, "\\begin{lstlisting}[escapechar=\xb7]\n");
 402         BEGIN(listing);
 403 }
 404
 405 <listing>\n*{ANY_COMMAND} {
 406         fprintf(yyout, "\n\\end{lstlisting}");
 407         yyless(0);
 408         BEGIN(l2l_last_yystart);
 409 }
 410
 411 <listing>\<§§I> {
 412         if (l2l_li_italic) {
 413                 L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "\xb7");
 414                 l2l_li_italic = 0;
 415         }
 416         else {
 417                 L2L_YY_APPEND_OR_ECHO(l2l_buf_ptr, "\xb7\\itshape ");
 418                 l2l_li_italic = 1;
 419         }
 420 }
 421
 422 <listing>§§\n /* ignore => lstlisting will insert appropriate arrows */;
 423
 424 <listing>. ECHO;
 425
 426         /*
 427          * images/boxes
 428          */
 429
 430 @(B|KT):{WHITESPACE}* {
 431         _Bool is_image = 0;
 432         _Bool is_box   = 0;
 433
 434         if (! strncmp(yytext, "@B:", 3))
 435                 is_image = 1;
 436         else if (! strncmp(yytext, "@KT:", 4))
 437                 is_box = 1;
 438
 439         if (l2l_scanner_state != L2L_FIGURE) {
 440                 if (is_box)
 441                         fprintf(yyout, "\\begin{l2lbox}\n");
 442                 else
 443                         fprintf(yyout, "\\begin{figure}\n");
 444                 l2l_scanner_state = L2L_FIGURE;
 445         }
 446         else {
 447                 l2l_scanner_state = L2L_BODY;
 448         }
 449
 450         l2l_buf_ptr = &l2l_caption;
 451         if (is_image)
 452                 BEGIN(caption);
 453         else if (is_box)
 454                 BEGIN(box_caption);
 455         else
 456                 assert(0);
 457 }
 458
 459 @Bi:.*\n {
 460         char *filename;
 461
 462         yytext[yyleng - 1] = '\0';
 463
 464         filename = yytext + strlen("@Bi:");
 465         while (isspace((int)*filename))
 466                 ++filename;
 467
 468         if (l2l_scanner_state != L2L_FIGURE) {
 469                 fprintf(yyout, "\\begin{figure}\n");
 470                 l2l_scanner_state = L2L_FIGURE;
 471         }
 472         else {
 473                 l2l_scanner_state = L2L_BODY;
 474         }
 475
 476         fprintf(yyout, "\\includegraphics[width=\\columnwidth]{%s}\n", filename);
 477
 478         if (l2l_scanner_state == L2L_BODY)
 479                 fprintf(yyout, "\\end{figure}\n");
 480 }
 481
 482 @KL: {
 483         if (l2l_scanner_state != L2L_FIGURE) {
 484                 fprintf(yyout, "\\begin{l2lbox}\n");
 485                 l2l_scanner_state = L2L_FIGURE;
 486         }
 487         else {
 488                 l2l_scanner_state = L2L_BODY;
 489         }
 490
 491         l2l_last_yystart = box;
 492         BEGIN(box);
 493 }
 494
 495 <box>@(KE|L):{WHITESPACE}* {
 496         fprintf(yyout, "\\end{l2lbox}");
 497         l2l_scanner_state = L2L_BODY;
 498         l2l_last_yystart = INITIAL;
 499         BEGIN(l2l_last_yystart);
 500 }
 501
 502 <caption,box_caption>{ANY_COMMAND} {
 503         if (l2l_buf_ptr) {
 504                 l2l_strbuf_chomp(l2l_buf_ptr);
 505                 l2l_buf_ptr = NULL;
 506         }
 507
 508         if (l2l_caption.len) {
 509                 fprintf(yyout, "\\caption*{%s}\n", l2l_caption.data);
 510                 L2L_STRBUF_CLEAR(&l2l_caption);
 511         }
 512
 513         if ((l2l_scanner_state == L2L_BODY) && (YY_START != box_caption))
 514                 fprintf(yyout, "\\end{figure}\n\n");
 515
 516         yyless(0);
 517         if (YY_START == caption)
 518                 BEGIN(l2l_last_yystart);
 519         else if (YY_START == box_caption) {
 520                 l2l_last_yystart = box;
 521                 BEGIN(box);
 522         }
 523         else
 524                 assert(0);
 525 }
 526
 527 <caption,box_caption>{COMMENT} { /* ignore */ }
 528
 529 <caption,box_caption>.|\n {
 530         if (l2l_buf_ptr)
 531                 if (l2l_strbuf_append(l2l_buf_ptr, "%s", yytext))
 532                         YY_FATAL_ERROR("ERROR: internal error");
 533         /* else ignore */
 534 }
 535
 536         /*
 537          * infos
 538          */
 539
 540 @IT:{WHITESPACE}* {
 541         l2l_buf_ptr = &l2l_ititle;
 542         BEGIN(title);
 543 }
 544
 545 <title>{ANY_COMMAND} {
 546         if (l2l_buf_ptr) {
 547                 l2l_strbuf_chomp(l2l_buf_ptr);
 548                 l2l_buf_ptr = NULL;
 549         }
 550
 551         if (l2l_ititle.len) {
 552                 fprintf(yyout, "\\subsection*{\\rule{\\columnwidth}{1pt}"
 553                                 "\\newline %s}\n", l2l_ititle.data);
 554                 L2L_STRBUF_CLEAR(&l2l_ititle);
 555         }
 556
 557         yyless(0);
 558         BEGIN(l2l_last_yystart);
 559 }
 560
 561 <title>{COMMENT} { /* ignore */ }
 562
 563 <title>.|\n {
 564         if (l2l_buf_ptr)
 565                 if (l2l_strbuf_append(l2l_buf_ptr, "%s", yytext))
 566                         YY_FATAL_ERROR("ERROR: internal error");
 567         /* else ignore */
 568 }
 569
 570 @IL: { /* ignore */ }
 571
 572 @IE: { /* ignore */ }
 573
 574         /*
 575          * tables
 576          */
 577
 578 @TT: /* TODO */;
 579
 580 @TH: /* TODO */;
 581
 582 @TL: /* TODO */;
 583
 584 @TE: /* TODO */;
 585
 586         /* let all other rules that match "@L:" have a higher preceedence */
 587 @L:{WHITESPACE}* { /* nothing to do */ }
 588
 589 <<EOF>> {
 590         if (l2l_scanner_state == L2L_BODY) {
 591                 fprintf(yyout, "\\end{document}\n");
 592         }
 593         else
 594                 YY_FATAL_ERROR("ERROR: incomplete document");
 595
 596         l2l_strbuf_destroy(&l2l_category);
 597         l2l_strbuf_destroy(&l2l_keyword);
 598         l2l_strbuf_destroy(&l2l_title);
 599         l2l_strbuf_destroy(&l2l_headline);
 600         l2l_strbuf_destroy(&l2l_author);
 601         l2l_strbuf_destroy(&l2l_abstract);
 602
 603         l2l_strbuf_destroy(&l2l_caption);
 604         l2l_strbuf_destroy(&l2l_title);
 605
 606         yyterminate();
 607 }
 608
 609 %%
 610
 611 static int
 612 l2l_strbuf_append(l2l_strbuf_t *buf, const char *fmt, ...)
 613 {
 614         size_t  str_len;
 615         va_list ap;
 616
 617         int status;
 618
 619         if ((! buf) || (! fmt))
 620                 return 0;
 621
 622         va_start(ap, fmt);
 623         status = vsnprintf(NULL, 0, fmt, ap);
 624         va_end(ap);
 625
 626         if (status <= 0)
 627                 return -1;
 628
 629         str_len = (size_t)status;
 630
 631         if (str_len > L2L_STRBUF_FREE(buf)) {
 632                 char  *new_data;
 633                 size_t new_size = 2 * buf->size;
 634
 635                 if (str_len > buf->size)
 636                         new_size += str_len;
 637
 638                 new_data = realloc(buf->data, new_size + 1);
 639                 if (! new_data) {
 640                         l2l_strbuf_destroy(buf);
 641                         return -1;
 642                 }
 643
 644                 buf->data = new_data;
 645                 buf->size = new_size;
 646         }
 647         assert(buf->len + str_len <= buf->size);
 648
 649         va_start(ap, fmt);
 650         status = vsnprintf(L2L_STRBUF_END(buf), L2L_STRBUF_FREE(buf) + 1, fmt, ap);
 651         va_end(ap);
 652
 653         if (status <= 0)
 654                 return -1;
 655
 656         assert((size_t)status == str_len);
 657         buf->len += str_len;
 658         buf->data[buf->len] = '\0';
 659         return 0;
 660 } /* l2l_strbuf_append */
 661
 662 static void
 663 l2l_strbuf_chomp(l2l_strbuf_t *buf)
 664 {
 665         if (! buf)
 666                 return;
 667
 668         while (buf->len && isspace((int)buf->data[buf->len - 1])) {
 669                 buf->data[buf->len - 1] = '\0';
 670                 --buf->len;
 671         }
 672 } /* l2l_strbuf_chomp */
 673
 674 static void
 675 l2l_strbuf_destroy(l2l_strbuf_t *buf)
 676 {
 677         if (! buf)
 678                 return;
 679
 680         if (buf->data)
 681                 free(buf->data);
 682         memset(buf, 0, sizeof(*buf));
 683 } /* l2l_strbuf_destroy */
 684
 685 /* vim: set tw=78 sw=4 ts=4 noexpandtab : */
 686