mdw@git.distorted.org.uk Git - quine/blob - qqlib.c

   1 /* -*-c-*-
   2  *
   3  * $Id$
   4  *
   5  * Useful library of tools for quines
   6  *
   7  * (c) 1999 Mark Wooding
   8  */
   9
  10 /*----- Licensing notice --------------------------------------------------*
  11  *
  12  * This file is part of Quine
  13  *
  14  * Quine is free software; you can redistribute it and/or modify
  15  * it under the terms of the GNU General Public License as published by
  16  * the Free Software Foundation; either version 2 of the License, or
  17  * (at your option) any later version.
  18  *
  19  * Quine is distributed in the hope that it will be useful,
  20  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  21  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  22  * GNU General Public License for more details.
  23  *
  24  * You should have received a copy of the GNU General Public License
  25  * along with Quine; if not, write to the Free Software Foundation,
  26  * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
  27  *
  28  * However, when this source text is embedded in a file by the Quine
  29  * program, you may do anything you like with the resulting text;
  30  * distribution and modification are not limited by the General Public
  31  * License.
  32  */
  33
  34 /*----- Header files ------------------------------------------------------*/
  35
  36 /* --- ANSI headers --- */
  37
  38 #include <errno.h>
  39 #include <stdio.h>
  40 #include <stdlib.h>
  41 #include <string.h>
  42
  43 /* --- POSIX headers --- */
  44
  45 #ifndef QUINE_PORTABLE
  46 #  include <sys/types.h>
  47 #  include <sys/fcntl.h>
  48 #  include <sys/stat.h>
  49 #  include <unistd.h>
  50 #endif
  51
  52 /* --- Local headers --- */
  53
  54 #include "quine.h"
  55
  56 /*----- Macro hacking -----------------------------------------------------*/
  57
  58 #ifdef QUINE_PORTABLE
  59 #  define PORT(x) x
  60 #  define NPORT(x)
  61 #else
  62 #  define PORT(x)
  63 #  define NPORT(x) x
  64 #endif
  65
  66 /*----- Main code ---------------------------------------------------------*/
  67
  68 /* --- @qq_xlate@ --- *
  69  *
  70  * Arguments:   @FILE *fp@ = output file handle
  71  *              @const char *p@ = pointer to encoded text
  72  *
  73  * Returns:     ---
  74  *
  75  * Use:         Writes the decoded string to the given file handle.
  76  */
  77
  78 void qq_xlate(FILE *fp, const char *p)
  79 {
  80   while (*p) {
  81     if (*p == '%') {
  82       p++;
  83       switch (*p) {
  84         case 'q': fputc('\"', fp); break;
  85         case 'b': fputc('\\', fp); break;
  86         case 't': fputc('\t', fp); break;
  87         case 'n': fputc('\n', fp); break;
  88         case 'a': fputc('\a', fp); break;
  89         case 'r': fputc('\r', fp); break;
  90         case '0': fputc('\0', fp); break;
  91         case '%': fputc('%', fp);  break;
  92         case 'x': {
  93           unsigned char ch = 0;
  94           p++;
  95           while (*p != '%') {
  96             unsigned int x = *p++;
  97             x -= '0';
  98             if (x >= 10) x -= 'a' - '0' - 10;
  99             if (x >= 16) x -= 'A' - 'a';
 100             ch = (ch << 4) + x;
 101           }
 102           fputc(ch, fp);
 103         } break;
 104         default:
 105           p--;
 106           break;
 107       }
 108     } else
 109       fputc(*p, fp);
 110     p++;
 111   }
 112 }
 113
 114 /* --- @qq_file@ --- *
 115  *
 116  * Arguments:   @FILE *fp@ = output file handle
 117  *              @const char **p@ = pointer to the output array
 118  *
 119  * Returns:     ---
 120  *
 121  * Use:         Writes the contents of a file to the output.
 122  */
 123
 124 void qq_file(FILE *fp, const char **p)
 125 {
 126   while (*p)
 127     qq_xlate(fp, *p++);
 128 }
 129
 130 /* --- @qq_head@ --- *
 131  *
 132  * Arguments:   @FILE *fp@ = output file handle
 133  *
 134  * Returns:     ---
 135  *
 136  * Use:         Writes the head of a `qqout.c' file.
 137  */
 138
 139 void qq_head(FILE *fp)
 140 {
 141   fputs("/* quine output file */\n\n", fp);
 142 }
 143
 144 /* --- @qq_body@ --- *
 145  *
 146  * Arguments:   @FILE *fp@ = output file handle
 147  *              @const char ***p@ = pointer to main table
 148  *
 149  * Returns:     ---
 150  *
 151  * Use:         Writes the body table of a `qqout.c' file.
 152  */
 153
 154 void qq_body(FILE *fp, const char ***p)
 155 {
 156   size_t fno = 0;
 157   const char **q;
 158
 159   fputs("/* --- file contents tables --- */\n\n", fp);
 160   while (*p) {
 161     q = *p;
 162     fprintf(fp, "static const char *qq__c_%lx[] = {\n", (unsigned long)fno);
 163     fprintf(fp, "/* Filename: */ \"%s\",\n", *q++);
 164     if (strncmp(*q, "%!", 2) == 0)
 165       fprintf(fp, "/* Mode: */ \"%s\",\n", *q++);
 166     while (*q)
 167       fprintf(fp, "\"%s\",\n", *q++);
 168     fputs("0\n};\n\n", fp);
 169     p++;
 170     fno++;
 171   }
 172 }
 173
 174 /* --- @qq_tail@ --- *
 175  *
 176  * Arguments:   @FILE *fp@ = output file handle
 177  *              @const char **qql@ = pointer to qqlib file array
 178  *              @size_t fno@ = number of files written
 179  *              @const char *fn@ = name of `qqout.c' file
 180  *
 181  * Returns:     ---
 182  *
 183  * Use:         Writes the head of a `qqout.c' file.
 184  */
 185
 186 void qq_tail(FILE *fp, const char **qql, size_t fno, const char *fn)
 187 {
 188   const char **p;
 189   size_t i;
 190
 191   /* --- Write out the qqlib array --- */
 192
 193   fputs("/* --- qqlib code --- */\n\n"
 194         "const char *qq_qqlib[] = {\n", fp);
 195   for (p = qql; *p; p++)
 196     fprintf(fp, "\"%s\",\n", *p);
 197   fputs("0\n};\n\n", fp);
 198
 199   /* --- Build the main array --- */
 200
 201   fputs("/* --- table of files to output --- */\n\n"
 202         "const char **qq_table[] = {\n", fp);
 203   for (i = 0; i < fno; i++)
 204     fprintf(fp, "  qq__c_%lx,\n", (unsigned long)i);
 205   fputs("  0\n};\n\n", fp);
 206
 207   /* --- Now output the qqlib code --- */
 208
 209   fputs("#define QQ_OUT\n\n", fp);
 210   qq_file(fp, qql);
 211
 212   /* --- Finally write the code to write everything out --- */
 213
 214   fprintf(fp,
 215           "/* --- quine output routines --- */\n\n"
 216           "void qq_dump(FILE *fp) {\n"
 217           "  qq__dump(fp, qq_table, qq_qqlib, \"%s\", %lu);\n"
 218           "}\n"
 219           "int qq_create(void) {\n"
 220           "  return (qq__create(qq_table, qq_qqlib, \"%s\", %lu));\n"
 221           "}\n\n",
 222           fn, (unsigned long)fno, fn, (unsigned long)fno);
 223 }
 224
 225 /* --- @qq_mkfile@ --- *
 226  *
 227  * Arguments:   @const char *fn@ = pointer to a filename
 228  *              @int mode@ = file mode to use (only in Unix-specific version)
 229  *
 230  * Returns:     A handle for the created file.
 231  *
 232  * Use:         Creates a file, and leading directories and stuff.
 233  */
 234
 235 #ifdef QUINE_PORTABLE
 236 FILE *qq_mkfile(const char *fn)
 237 {
 238   return (fopen(fn, "w"));
 239 }
 240 #else
 241 FILE *qq_mkfile(const char *fn, int mode)
 242 {
 243   char buf[FILENAME_MAX];
 244   char *p;
 245   int fd;
 246
 247   strcpy(buf, fn);
 248   p = strchr(buf, '/');
 249   for (;;) {
 250     if (!p)
 251       break;
 252     *p = 0;
 253     mkdir(buf, 0777);
 254     *p = '/';
 255     p = strchr(p + 1, '/');
 256   }
 257
 258   fd = open(fn, O_WRONLY|O_CREAT|O_TRUNC, mode);
 259   return (fd >=0 ? fdopen(fd, "w") : 0);
 260 }
 261 #endif
 262
 263 #ifdef QQ_OUT
 264
 265 /* --- @qq__dump@ --- *
 266  *
 267  * Arguments:   @FILE *fp@ = file to dump on
 268  *              @const char ***p@ = pointer to main table
 269  *              @const char **qql@ = pointer to qqlib code
 270  *              @const char *fn@ = name of `qqout.c' file
 271  *              @size_t fno@ = number of files to be output
 272  *
 273  * Returns:     ---
 274  *
 275  * Use:         Outputs the entire source code to a given file.
 276  */
 277
 278 static void qq__dump(FILE *fp, const char ***p, const char **qql,
 279                      const char *fn, size_t fno)
 280 {
 281   const char ***q = p;
 282
 283   while (*q) {
 284     fprintf(fp, "******** %s\n\n", **q);
 285     qq_file(fp, *q + 1);
 286     q++;
 287   }
 288   fprintf(fp, "******** %s\n\n", fn);
 289   qq_head(fp);
 290   qq_body(fp, p);
 291   qq_tail(fp, qql, fno, fn);
 292 }
 293
 294 /* --- @qq__create@ --- *
 295  *
 296  * Arguments:   @const char ***p@ = pointer to main table
 297  *              @const char **qql@ = pointer to qqlib code
 298  *              @const char *fn@ = name of `qqout.c' file
 299  *              @size_t fno@ = number of files to be output
 300  *
 301  * Returns:     Zero if all went well, else nonzero.
 302  *
 303  * Use:         Rebuilds the original source distribution.
 304  */
 305
 306 static int qq__create(const char ***p, const char **qql,
 307                       const char *fn, size_t fno)
 308 {
 309   FILE *fp;
 310   const char ***q = p;
 311
 312   while (*q) {
 313     const char **qq = *q + 1;
 314
 315 #ifdef QUINE_PORTABLE
 316     if (strncmp(*qq, "%!", 2) == 0)
 317       qq++;
 318     fp = qq_mkfile(*qq);
 319 #else
 320     if (strncmp(*qq, "%!", 2) == 0) {
 321       fp = qq_mkfile(**q, (int)strtol(*qq + 2, 0, 8));
 322       qq++;
 323     } else
 324       fp = qq_mkfile(**q, 0666);
 325 #endif
 326
 327     if (!fp)
 328       return (-1);
 329     qq_file(fp, qq);
 330     if (fclose(fp))
 331       return (-1);
 332     q++;
 333   }
 334   fp = qq_mkfile(fn, 0666);
 335   if (!fp)
 336     return (-1);
 337   qq_head(fp);
 338   qq_body(fp, p);
 339   qq_tail(fp, qql, fno, fn);
 340   if (fclose(fp))
 341     return (-1);
 342   return (0);
 343 }
 344
 345 #endif
 346
 347 /*----- That's all, folks -------------------------------------------------*/