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

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