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- /*
- * ckconfig.c
- *
- * Copyright (C) 1991, 1992, Thomas G. Lane.
- * This file is part of the Independent JPEG Group's software.
- * For conditions of distribution and use, see the accompanying README file.
- */
-
- /*
- * This program is intended to help you determine how to configure the JPEG
- * software for installation on a particular system. The idea is to try to
- * compile and execute this program. If your compiler fails to compile the
- * program, make changes as indicated in the comments below. Once you can
- * compile the program, run it, and it will tell you how to set the various
- * switches in jconfig.h and in your Makefile.
- *
- * This could all be done automatically if we could assume we were on a Unix
- * system, but we don't want to assume that, so you'll have to edit and
- * recompile this program until it works.
- *
- * As a general rule, each time you try to compile this program,
- * pay attention only to the *first* error message you get from the compiler.
- * Many C compilers will issue lots of spurious error messages once they
- * have gotten confused. Go to the line indicated in the first error message,
- * and read the comments preceding that line to see what to change.
- *
- * Almost all of the edits you may need to make to this program consist of
- * changing a line that reads "#define SOME_SYMBOL" to "#undef SOME_SYMBOL",
- * or vice versa. This is called defining or undefining that symbol.
- */
-
-
- /* First we must see if your system has the include files we need.
- * We start out with the assumption that your system follows the ANSI
- * conventions for include files. If you get any error in the next dozen
- * lines, undefine INCLUDES_ARE_ANSI.
- */
-
- #define INCLUDES_ARE_ANSI /* replace 'define' by 'undef' if error here */
-
- #ifdef INCLUDES_ARE_ANSI /* this will be skipped if you undef... */
- #include <stdio.h> /* If you ain't got this, you ain't got C. */
- #ifdef __SASC /* Amiga SAS C provides size_t in stddef.h. */
- #include <stddef.h> /* (They are wrong...) */
- #endif
- #include <string.h> /* size_t might be here too. */
- typedef size_t my_size_t; /* The payoff: do we have size_t now? */
- #include <stdlib.h> /* Check other ANSI includes we use. */
- #endif
-
-
- /* If your system doesn't follow the ANSI conventions, we have to figure out
- * what it does follow. If you didn't get an error before this line, you can
- * ignore everything down to "#define HAVE_ANSI_DEFINITIONS".
- */
-
- #ifndef INCLUDES_ARE_ANSI /* skip these tests if INCLUDES_ARE_ANSI */
-
- #include <stdio.h> /* If you ain't got this, you ain't got C. */
-
- /* jinclude.h will try to include <sys/types.h> if you don't set
- * INCLUDES_ARE_ANSI. We need to test whether that include file is provided.
- * If you get an error here, undefine HAVE_TYPES_H.
- */
-
- #define HAVE_TYPES_H
-
- #ifdef HAVE_TYPES_H
- #include <sys/types.h>
- #endif
-
- /* We have to see if your string functions are defined by
- * strings.h (BSD convention) or string.h (everybody else).
- * We try the non-BSD convention first; define BSD if the compiler
- * says it can't find string.h.
- */
-
- #undef BSD
-
- #ifdef BSD
- #include <strings.h>
- #else
- #include <string.h>
- #endif
-
- /* Usually size_t is defined in stdio.h, sys/types.h, and/or string.h.
- * If not, you'll get an error on the "typedef size_t my_size_t;" line below.
- * In that case, you'll have to search through your system library to
- * figure out which include file defines "size_t". Look for a line that
- * says "typedef something-or-other size_t;" (stddef.h and stdlib.h are
- * good places to look first). Then, change the line below that says
- * "#include <someincludefile.h>" to instead include the file
- * you found size_t in, and define NEED_SPECIAL_INCLUDE.
- */
-
- #undef NEED_SPECIAL_INCLUDE /* assume we DON'T need it, for starters */
-
- #ifdef NEED_SPECIAL_INCLUDE
- #include <someincludefile.h>
- #endif
-
- typedef size_t my_size_t; /* The payoff: do we have size_t now? */
-
-
- #endif /* INCLUDES_ARE_ANSI */
-
-
-
- /* The next question is whether your compiler supports ANSI-style function
- * definitions. You need to know this in order to choose between using
- * makefile.ansi and using makefile.unix.
- * The #define line below is set to assume you have ANSI function definitions.
- * If you get an error in this group of lines, undefine HAVE_ANSI_DEFINITIONS.
- */
-
- #define HAVE_ANSI_DEFINITIONS
-
- #ifdef HAVE_ANSI_DEFINITIONS
- int testfunction (int arg1, int * arg2); /* check prototypes */
-
- struct methods_struct { /* check method-pointer declarations */
- int (*error_exit) (char *msgtext);
- int (*trace_message) (char *msgtext);
- int (*another_method) (void);
- };
-
- int testfunction (int arg1, int * arg2) /* check definitions */
- {
- return arg2[arg1];
- }
-
- int testfunction1 (void) /* check void arg list */
- {
- return 0;
- }
- #endif
-
-
- /* Now we want to find out if your compiler knows what "unsigned char" means.
- * If you get an error on the "unsigned char un_char;" line,
- * then undefine HAVE_UNSIGNED_CHAR.
- */
-
- #define HAVE_UNSIGNED_CHAR
-
- #ifdef HAVE_UNSIGNED_CHAR
- unsigned char un_char;
- #endif
-
-
- /* Now we want to find out if your compiler knows what "unsigned short" means.
- * If you get an error on the "unsigned short un_short;" line,
- * then undefine HAVE_UNSIGNED_SHORT.
- */
-
- #define HAVE_UNSIGNED_SHORT
-
- #ifdef HAVE_UNSIGNED_SHORT
- unsigned short un_short;
- #endif
-
-
- /* Now we want to find out if your compiler understands type "void".
- * If you get an error anywhere in here, undefine HAVE_VOID.
- */
-
- #define HAVE_VOID
-
- #ifdef HAVE_VOID
- typedef void * void_ptr; /* check void * */
- typedef void (*void_func) (); /* check ptr to function returning void */
-
- void testfunction2 (arg1, arg2) /* check void function result */
- void_ptr arg1;
- void_func arg2;
- {
- char * locptr = (char *) arg1; /* check casting to and from void * */
- arg1 = (void *) locptr;
- (*arg2) (1, 2); /* check call of fcn returning void */
- }
- #endif
-
-
- /* Now we want to find out if your compiler knows what "const" means.
- * If you get an error here, undefine HAVE_CONST.
- */
-
- #define HAVE_CONST
-
- #ifdef HAVE_CONST
- static const int carray[3] = {1, 2, 3};
-
- int testfunction3 (arg1)
- const int arg1;
- {
- return carray[arg1];
- }
- #endif
-
-
-
- /************************************************************************
- * OK, that's it. You should not have to change anything beyond this
- * point in order to compile and execute this program. (You might get
- * some warnings, but you can ignore them.)
- * When you run the program, it will make a couple more tests that it
- * can do automatically, and then it will print out a summary of the changes
- * that you need to make to the makefile and jconfig.h.
- ************************************************************************
- */
-
-
- static int any_changes = 0;
-
- int new_change ()
- {
- if (! any_changes) {
- printf("\nMost of the changes recommended by this program can be made either\n");
- printf("by editing jconfig.h, or by adding -Dsymbol switches to the CFLAGS\n");
- printf("line in your Makefile. (Some PC compilers expect /Dsymbol instead.)\n");
- printf("The CFLAGS method is simpler, but if your compiler doesn't support -D,\n");
- printf("then you must change jconfig.h. Also, it's best to change jconfig.h\n");
- printf("if you plan to use the JPEG software as a library for other programs.\n");
- any_changes = 1;
- }
- printf("\n"); /* blank line before each problem report */
- return 0;
- }
-
-
- int test_char_sign (arg)
- int arg;
- {
- if (arg == 189) { /* expected result for unsigned char */
- new_change();
- printf("You should add -DCHAR_IS_UNSIGNED to CFLAGS,\n");
- printf("or else remove the /* */ comment marks from the line\n");
- printf("/* #define CHAR_IS_UNSIGNED */ in jconfig.h.\n");
- printf("(Be sure to delete the space before the # character too.)\n");
- }
- else if (arg != -67) { /* expected result for signed char */
- new_change();
- printf("Hmm, it seems 'char' is less than eight bits wide on your machine.\n");
- printf("I fear the JPEG software will not work at all.\n");
- }
- return 0;
- }
-
-
- int test_shifting (arg)
- long arg;
- /* See whether right-shift on a long is signed or not. */
- {
- long res = arg >> 4;
-
- if (res == 0x80817F4L) { /* expected result for unsigned */
- new_change();
- printf("You must add -DRIGHT_SHIFT_IS_UNSIGNED to CFLAGS,\n");
- printf("or else remove the /* */ comment marks from the line\n");
- printf("/* #define RIGHT_SHIFT_IS_UNSIGNED */ in jconfig.h.\n");
- }
- else if (res != -0x7F7E80CL) { /* expected result for signed */
- new_change();
- printf("Right shift isn't acting as I expect it to.\n");
- printf("I fear the JPEG software will not work at all.\n");
- }
- return 0;
- }
-
-
- int main (argc, argv)
- int argc;
- char ** argv;
- {
- char signed_char_check = (char) (-67);
-
- printf("Results of configuration check for Independent JPEG Group's software:\n");
- printf("\nIf there's not a specific makefile provided for your compiler,\n");
- #ifdef HAVE_ANSI_DEFINITIONS
- printf("you should use makefile.ansi as the starting point for your Makefile.\n");
- #else
- printf("you should use makefile.unix as the starting point for your Makefile.\n");
- #endif
-
- /* Check whether we have all the ANSI features, */
- /* and whether this agrees with __STDC__ being predefined. */
- #ifdef __STDC__
- #define HAVE_STDC /* ANSI compilers won't allow redefining __STDC__ */
- #endif
-
- #ifdef HAVE_ANSI_DEFINITIONS
- #ifdef HAVE_UNSIGNED_CHAR
- #ifdef HAVE_UNSIGNED_SHORT
- #ifdef HAVE_CONST
- #define HAVE_ALL_ANSI_FEATURES
- #endif
- #endif
- #endif
- #endif
-
- #ifdef HAVE_ALL_ANSI_FEATURES
- #ifndef HAVE_STDC
- new_change();
- printf("Your compiler doesn't claim to be ANSI-compliant, but it is close enough\n");
- printf("for me. Either add -DHAVE_STDC to CFLAGS, or add #define HAVE_STDC at the\n");
- printf("beginning of jconfig.h.\n");
- #define HAVE_STDC
- #endif
- #else /* !HAVE_ALL_ANSI_FEATURES */
- #ifdef HAVE_STDC
- new_change();
- printf("Your compiler claims to be ANSI-compliant, but it is lying!\n");
- printf("Delete the line #define HAVE_STDC near the beginning of jconfig.h.\n");
- #undef HAVE_STDC
- #endif
- #endif /* HAVE_ALL_ANSI_FEATURES */
-
- #ifndef HAVE_STDC
-
- #ifdef HAVE_ANSI_DEFINITIONS
- new_change();
- printf("You should add -DPROTO to CFLAGS, or else take out the several\n");
- printf("#ifdef/#else/#endif lines surrounding #define PROTO in jconfig.h.\n");
- printf("(Leave only one #define PROTO line.)\n");
- #endif
-
- #ifdef HAVE_UNSIGNED_CHAR
- #ifdef HAVE_UNSIGNED_SHORT
- new_change();
- printf("You should add -DHAVE_UNSIGNED_CHAR and -DHAVE_UNSIGNED_SHORT\n");
- printf("to CFLAGS, or else take out the #ifdef HAVE_STDC/#endif lines\n");
- printf("surrounding #define HAVE_UNSIGNED_CHAR and #define HAVE_UNSIGNED_SHORT\n");
- printf("in jconfig.h.\n");
- #else /* only unsigned char */
- new_change();
- printf("You should add -DHAVE_UNSIGNED_CHAR to CFLAGS,\n");
- printf("or else move #define HAVE_UNSIGNED_CHAR outside the\n");
- printf("#ifdef HAVE_STDC/#endif lines surrounding it in jconfig.h.\n");
- #endif
- #else /* !HAVE_UNSIGNED_CHAR */
- #ifdef HAVE_UNSIGNED_SHORT
- new_change();
- printf("You should add -DHAVE_UNSIGNED_SHORT to CFLAGS,\n");
- printf("or else move #define HAVE_UNSIGNED_SHORT outside the\n");
- printf("#ifdef HAVE_STDC/#endif lines surrounding it in jconfig.h.\n");
- #endif
- #endif /* HAVE_UNSIGNED_CHAR */
-
- #ifdef HAVE_CONST
- new_change();
- printf("You should delete the #define const line from jconfig.h.\n");
- #endif
-
- #endif /* HAVE_STDC */
-
- test_char_sign((int) signed_char_check);
-
- test_shifting(-0x7F7E80B1L);
-
- #ifndef HAVE_VOID
- new_change();
- printf("You should add -Dvoid=char to CFLAGS,\n");
- printf("or else remove the /* */ comment marks from the line\n");
- printf("/* #define void char */ in jconfig.h.\n");
- printf("(Be sure to delete the space before the # character too.)\n");
- #endif
-
- #ifdef INCLUDES_ARE_ANSI
- #ifndef __STDC__
- new_change();
- printf("You should add -DINCLUDES_ARE_ANSI to CFLAGS, or else add\n");
- printf("#define INCLUDES_ARE_ANSI at the beginning of jinclude.h (NOT jconfig.h).\n");
- #endif
- #else /* !INCLUDES_ARE_ANSI */
- #ifdef __STDC__
- new_change();
- printf("You should add -DNONANSI_INCLUDES to CFLAGS, or else add\n");
- printf("#define NONANSI_INCLUDES at the beginning of jinclude.h (NOT jconfig.h).\n");
- #endif
- #ifdef NEED_SPECIAL_INCLUDE
- new_change();
- printf("In jinclude.h, change the line reading #include <sys/types.h>\n");
- printf("to instead include the file you found size_t in.\n");
- #else /* !NEED_SPECIAL_INCLUDE */
- #ifndef HAVE_TYPES_H
- new_change();
- printf("In jinclude.h, delete the line reading #include <sys/types.h>.\n");
- #endif
- #endif /* NEED_SPECIAL_INCLUDE */
- #ifdef BSD
- new_change();
- printf("You should add -DBSD to CFLAGS, or else add\n");
- printf("#define BSD at the beginning of jinclude.h (NOT jconfig.h).\n");
- #endif
- #endif /* INCLUDES_ARE_ANSI */
-
- if (any_changes) {
- printf("\nI think that's everything...\n");
- } else {
- printf("\nI think jconfig.h is OK as distributed.\n");
- }
-
- return any_changes;
- }
-