Home | History | Annotate | Download | only in jpeg-6b
      1 /*
      2  * ckconfig.c
      3  *
      4  * Copyright (C) 1991-1994, Thomas G. Lane.
      5  * This file is part of the Independent JPEG Group's software.
      6  * For conditions of distribution and use, see the accompanying README file.
      7  */
      8 
      9 /*
     10  * This program is intended to help you determine how to configure the JPEG
     11  * software for installation on a particular system.  The idea is to try to
     12  * compile and execute this program.  If your compiler fails to compile the
     13  * program, make changes as indicated in the comments below.  Once you can
     14  * compile the program, run it, and it will produce a "jconfig.h" file for
     15  * your system.
     16  *
     17  * As a general rule, each time you try to compile this program,
     18  * pay attention only to the *first* error message you get from the compiler.
     19  * Many C compilers will issue lots of spurious error messages once they
     20  * have gotten confused.  Go to the line indicated in the first error message,
     21  * and read the comments preceding that line to see what to change.
     22  *
     23  * Almost all of the edits you may need to make to this program consist of
     24  * changing a line that reads "#define SOME_SYMBOL" to "#undef SOME_SYMBOL",
     25  * or vice versa.  This is called defining or undefining that symbol.
     26  */
     27 
     28 
     29 /* First we must see if your system has the include files we need.
     30  * We start out with the assumption that your system has all the ANSI-standard
     31  * include files.  If you get any error trying to include one of these files,
     32  * undefine the corresponding HAVE_xxx symbol.
     33  */
     34 
     35 #define HAVE_STDDEF_H		/* replace 'define' by 'undef' if error here */
     36 #ifdef HAVE_STDDEF_H		/* next line will be skipped if you undef... */
     37 #include <stddef.h>
     38 #endif
     39 
     40 #define HAVE_STDLIB_H		/* same thing for stdlib.h */
     41 #ifdef HAVE_STDLIB_H
     42 #include <stdlib.h>
     43 #endif
     44 
     45 #include <stdio.h>		/* If you ain't got this, you ain't got C. */
     46 
     47 /* We have to see if your string functions are defined by
     48  * strings.h (old BSD convention) or string.h (everybody else).
     49  * We try the non-BSD convention first; define NEED_BSD_STRINGS
     50  * if the compiler says it can't find string.h.
     51  */
     52 
     53 #undef NEED_BSD_STRINGS
     54 
     55 #ifdef NEED_BSD_STRINGS
     56 #include <strings.h>
     57 #else
     58 #include <string.h>
     59 #endif
     60 
     61 /* On some systems (especially older Unix machines), type size_t is
     62  * defined only in the include file <sys/types.h>.  If you get a failure
     63  * on the size_t test below, try defining NEED_SYS_TYPES_H.
     64  */
     65 
     66 #undef NEED_SYS_TYPES_H		/* start by assuming we don't need it */
     67 #ifdef NEED_SYS_TYPES_H
     68 #include <sys/types.h>
     69 #endif
     70 
     71 
     72 /* Usually type size_t is defined in one of the include files we've included
     73  * above.  If not, you'll get an error on the "typedef size_t my_size_t;" line.
     74  * In that case, first try defining NEED_SYS_TYPES_H just above.
     75  * If that doesn't work, you'll have to search through your system library
     76  * to figure out which include file defines "size_t".  Look for a line that
     77  * says "typedef something-or-other size_t;".  Then, change the line below
     78  * that says "#include <someincludefile.h>" to instead include the file
     79  * you found size_t in, and define NEED_SPECIAL_INCLUDE.  If you can't find
     80  * type size_t anywhere, try replacing "#include <someincludefile.h>" with
     81  * "typedef unsigned int size_t;".
     82  */
     83 
     84 #undef NEED_SPECIAL_INCLUDE	/* assume we DON'T need it, for starters */
     85 
     86 #ifdef NEED_SPECIAL_INCLUDE
     87 #include <someincludefile.h>
     88 #endif
     89 
     90 typedef size_t my_size_t;	/* The payoff: do we have size_t now? */
     91 
     92 
     93 /* The next question is whether your compiler supports ANSI-style function
     94  * prototypes.  You need to know this in order to choose between using
     95  * makefile.ansi and using makefile.unix.
     96  * The #define line below is set to assume you have ANSI function prototypes.
     97  * If you get an error in this group of lines, undefine HAVE_PROTOTYPES.
     98  */
     99 
    100 #define HAVE_PROTOTYPES
    101 
    102 #ifdef HAVE_PROTOTYPES
    103 int testfunction (int arg1, int * arg2); /* check prototypes */
    104 
    105 struct methods_struct {		/* check method-pointer declarations */
    106   int (*error_exit) (char *msgtext);
    107   int (*trace_message) (char *msgtext);
    108   int (*another_method) (void);
    109 };
    110 
    111 int testfunction (int arg1, int * arg2) /* check definitions */
    112 {
    113   return arg2[arg1];
    114 }
    115 
    116 int test2function (void)	/* check void arg list */
    117 {
    118   return 0;
    119 }
    120 #endif
    121 
    122 
    123 /* Now we want to find out if your compiler knows what "unsigned char" means.
    124  * If you get an error on the "unsigned char un_char;" line,
    125  * then undefine HAVE_UNSIGNED_CHAR.
    126  */
    127 
    128 #define HAVE_UNSIGNED_CHAR
    129 
    130 #ifdef HAVE_UNSIGNED_CHAR
    131 unsigned char un_char;
    132 #endif
    133 
    134 
    135 /* Now we want to find out if your compiler knows what "unsigned short" means.
    136  * If you get an error on the "unsigned short un_short;" line,
    137  * then undefine HAVE_UNSIGNED_SHORT.
    138  */
    139 
    140 #define HAVE_UNSIGNED_SHORT
    141 
    142 #ifdef HAVE_UNSIGNED_SHORT
    143 unsigned short un_short;
    144 #endif
    145 
    146 
    147 /* Now we want to find out if your compiler understands type "void".
    148  * If you get an error anywhere in here, undefine HAVE_VOID.
    149  */
    150 
    151 #define HAVE_VOID
    152 
    153 #ifdef HAVE_VOID
    154 /* Caution: a C++ compiler will insist on complete prototypes */
    155 typedef void * void_ptr;	/* check void * */
    156 #ifdef HAVE_PROTOTYPES		/* check ptr to function returning void */
    157 typedef void (*void_func) (int a, int b);
    158 #else
    159 typedef void (*void_func) ();
    160 #endif
    161 
    162 #ifdef HAVE_PROTOTYPES		/* check void function result */
    163 void test3function (void_ptr arg1, void_func arg2)
    164 #else
    165 void test3function (arg1, arg2)
    166      void_ptr arg1;
    167      void_func arg2;
    168 #endif
    169 {
    170   char * locptr = (char *) arg1; /* check casting to and from void * */
    171   arg1 = (void *) locptr;
    172   (*arg2) (1, 2);		/* check call of fcn returning void */
    173 }
    174 #endif
    175 
    176 
    177 /* Now we want to find out if your compiler knows what "const" means.
    178  * If you get an error here, undefine HAVE_CONST.
    179  */
    180 
    181 #define HAVE_CONST
    182 
    183 #ifdef HAVE_CONST
    184 static const int carray[3] = {1, 2, 3};
    185 
    186 #ifdef HAVE_PROTOTYPES
    187 int test4function (const int arg1)
    188 #else
    189 int test4function (arg1)
    190      const int arg1;
    191 #endif
    192 {
    193   return carray[arg1];
    194 }
    195 #endif
    196 
    197 
    198 /* If you get an error or warning about this structure definition,
    199  * define INCOMPLETE_TYPES_BROKEN.
    200  */
    201 
    202 #undef INCOMPLETE_TYPES_BROKEN
    203 
    204 #ifndef INCOMPLETE_TYPES_BROKEN
    205 typedef struct undefined_structure * undef_struct_ptr;
    206 #endif
    207 
    208 
    209 /* If you get an error about duplicate names,
    210  * define NEED_SHORT_EXTERNAL_NAMES.
    211  */
    212 
    213 #undef NEED_SHORT_EXTERNAL_NAMES
    214 
    215 #ifndef NEED_SHORT_EXTERNAL_NAMES
    216 
    217 int possibly_duplicate_function ()
    218 {
    219   return 0;
    220 }
    221 
    222 int possibly_dupli_function ()
    223 {
    224   return 1;
    225 }
    226 
    227 #endif
    228 
    229 
    230 
    231 /************************************************************************
    232  *  OK, that's it.  You should not have to change anything beyond this
    233  *  point in order to compile and execute this program.  (You might get
    234  *  some warnings, but you can ignore them.)
    235  *  When you run the program, it will make a couple more tests that it
    236  *  can do automatically, and then it will create jconfig.h and print out
    237  *  any additional suggestions it has.
    238  ************************************************************************
    239  */
    240 
    241 
    242 #ifdef HAVE_PROTOTYPES
    243 int is_char_signed (int arg)
    244 #else
    245 int is_char_signed (arg)
    246      int arg;
    247 #endif
    248 {
    249   if (arg == 189) {		/* expected result for unsigned char */
    250     return 0;			/* type char is unsigned */
    251   }
    252   else if (arg != -67) {	/* expected result for signed char */
    253     printf("Hmm, it seems 'char' is not eight bits wide on your machine.\n");
    254     printf("I fear the JPEG software will not work at all.\n\n");
    255   }
    256   return 1;			/* assume char is signed otherwise */
    257 }
    258 
    259 
    260 #ifdef HAVE_PROTOTYPES
    261 int is_shifting_signed (long arg)
    262 #else
    263 int is_shifting_signed (arg)
    264      long arg;
    265 #endif
    266 /* See whether right-shift on a long is signed or not. */
    267 {
    268   long res = arg >> 4;
    269 
    270   if (res == -0x7F7E80CL) {	/* expected result for signed shift */
    271     return 1;			/* right shift is signed */
    272   }
    273   /* see if unsigned-shift hack will fix it. */
    274   /* we can't just test exact value since it depends on width of long... */
    275   res |= (~0L) << (32-4);
    276   if (res == -0x7F7E80CL) {	/* expected result now? */
    277     return 0;			/* right shift is unsigned */
    278   }
    279   printf("Right shift isn't acting as I expect it to.\n");
    280   printf("I fear the JPEG software will not work at all.\n\n");
    281   return 0;			/* try it with unsigned anyway */
    282 }
    283 
    284 
    285 #ifdef HAVE_PROTOTYPES
    286 int main (int argc, char ** argv)
    287 #else
    288 int main (argc, argv)
    289      int argc;
    290      char ** argv;
    291 #endif
    292 {
    293   char signed_char_check = (char) (-67);
    294   FILE *outfile;
    295 
    296   /* Attempt to write jconfig.h */
    297   if ((outfile = fopen("jconfig.h", "w")) == NULL) {
    298     printf("Failed to write jconfig.h\n");
    299     return 1;
    300   }
    301 
    302   /* Write out all the info */
    303   fprintf(outfile, "/* jconfig.h --- generated by ckconfig.c */\n");
    304   fprintf(outfile, "/* see jconfig.doc for explanations */\n\n");
    305 #ifdef HAVE_PROTOTYPES
    306   fprintf(outfile, "#define HAVE_PROTOTYPES\n");
    307 #else
    308   fprintf(outfile, "#undef HAVE_PROTOTYPES\n");
    309 #endif
    310 #ifdef HAVE_UNSIGNED_CHAR
    311   fprintf(outfile, "#define HAVE_UNSIGNED_CHAR\n");
    312 #else
    313   fprintf(outfile, "#undef HAVE_UNSIGNED_CHAR\n");
    314 #endif
    315 #ifdef HAVE_UNSIGNED_SHORT
    316   fprintf(outfile, "#define HAVE_UNSIGNED_SHORT\n");
    317 #else
    318   fprintf(outfile, "#undef HAVE_UNSIGNED_SHORT\n");
    319 #endif
    320 #ifdef HAVE_VOID
    321   fprintf(outfile, "/* #define void char */\n");
    322 #else
    323   fprintf(outfile, "#define void char\n");
    324 #endif
    325 #ifdef HAVE_CONST
    326   fprintf(outfile, "/* #define const */\n");
    327 #else
    328   fprintf(outfile, "#define const\n");
    329 #endif
    330   if (is_char_signed((int) signed_char_check))
    331     fprintf(outfile, "#undef CHAR_IS_UNSIGNED\n");
    332   else
    333     fprintf(outfile, "#define CHAR_IS_UNSIGNED\n");
    334 #ifdef HAVE_STDDEF_H
    335   fprintf(outfile, "#define HAVE_STDDEF_H\n");
    336 #else
    337   fprintf(outfile, "#undef HAVE_STDDEF_H\n");
    338 #endif
    339 #ifdef HAVE_STDLIB_H
    340   fprintf(outfile, "#define HAVE_STDLIB_H\n");
    341 #else
    342   fprintf(outfile, "#undef HAVE_STDLIB_H\n");
    343 #endif
    344 #ifdef NEED_BSD_STRINGS
    345   fprintf(outfile, "#define NEED_BSD_STRINGS\n");
    346 #else
    347   fprintf(outfile, "#undef NEED_BSD_STRINGS\n");
    348 #endif
    349 #ifdef NEED_SYS_TYPES_H
    350   fprintf(outfile, "#define NEED_SYS_TYPES_H\n");
    351 #else
    352   fprintf(outfile, "#undef NEED_SYS_TYPES_H\n");
    353 #endif
    354   fprintf(outfile, "#undef NEED_FAR_POINTERS\n");
    355 #ifdef NEED_SHORT_EXTERNAL_NAMES
    356   fprintf(outfile, "#define NEED_SHORT_EXTERNAL_NAMES\n");
    357 #else
    358   fprintf(outfile, "#undef NEED_SHORT_EXTERNAL_NAMES\n");
    359 #endif
    360 #ifdef INCOMPLETE_TYPES_BROKEN
    361   fprintf(outfile, "#define INCOMPLETE_TYPES_BROKEN\n");
    362 #else
    363   fprintf(outfile, "#undef INCOMPLETE_TYPES_BROKEN\n");
    364 #endif
    365   fprintf(outfile, "\n#ifdef JPEG_INTERNALS\n\n");
    366   if (is_shifting_signed(-0x7F7E80B1L))
    367     fprintf(outfile, "#undef RIGHT_SHIFT_IS_UNSIGNED\n");
    368   else
    369     fprintf(outfile, "#define RIGHT_SHIFT_IS_UNSIGNED\n");
    370   fprintf(outfile, "\n#endif /* JPEG_INTERNALS */\n");
    371   fprintf(outfile, "\n#ifdef JPEG_CJPEG_DJPEG\n\n");
    372   fprintf(outfile, "#define BMP_SUPPORTED		/* BMP image file format */\n");
    373   fprintf(outfile, "#define GIF_SUPPORTED		/* GIF image file format */\n");
    374   fprintf(outfile, "#define PPM_SUPPORTED		/* PBMPLUS PPM/PGM image file format */\n");
    375   fprintf(outfile, "#undef RLE_SUPPORTED		/* Utah RLE image file format */\n");
    376   fprintf(outfile, "#define TARGA_SUPPORTED		/* Targa image file format */\n\n");
    377   fprintf(outfile, "#undef TWO_FILE_COMMANDLINE	/* You may need this on non-Unix systems */\n");
    378   fprintf(outfile, "#undef NEED_SIGNAL_CATCHER	/* Define this if you use jmemname.c */\n");
    379   fprintf(outfile, "#undef DONT_USE_B_MODE\n");
    380   fprintf(outfile, "/* #define PROGRESS_REPORT */	/* optional */\n");
    381   fprintf(outfile, "\n#endif /* JPEG_CJPEG_DJPEG */\n");
    382 
    383   /* Close the jconfig.h file */
    384   fclose(outfile);
    385 
    386   /* User report */
    387   printf("Configuration check for Independent JPEG Group's software done.\n");
    388   printf("\nI have written the jconfig.h file for you.\n\n");
    389 #ifdef HAVE_PROTOTYPES
    390   printf("You should use makefile.ansi as the starting point for your Makefile.\n");
    391 #else
    392   printf("You should use makefile.unix as the starting point for your Makefile.\n");
    393 #endif
    394 
    395 #ifdef NEED_SPECIAL_INCLUDE
    396   printf("\nYou'll need to change jconfig.h to include the system include file\n");
    397   printf("that you found type size_t in, or add a direct definition of type\n");
    398   printf("size_t if that's what you used.  Just add it to the end.\n");
    399 #endif
    400 
    401   return 0;
    402 }
    403