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1 | |
2 | /********************************************************************** | |
3 | ||
4 | Description of Guile's public config header mechanics: | |
5 | ----------------------------------------------------- | |
6 | ||
7 | Guile has four core headers: | |
8 | ||
9 | config.h: Guile's private automatically generated configuration | |
10 | header -- generated by configure.in and autoheader. *NOT* | |
11 | installed during "make install" and so may not be referred to by | |
12 | any public headers. | |
13 | ||
14 | libguile/_scm.h: Guile's private core header. _scm.h is not | |
15 | installed. It's only visible to the libguile sources | |
16 | themselves, and it includes config.h, the private config header. | |
17 | Among other things this file provides a place to make decisions | |
18 | based on the information gathered in config.h. | |
19 | ||
20 | libguile/scmconfig.h: Guile's public automatically generated | |
21 | configuration header -- generated at build time by concatenating | |
22 | the contents of libguile/scmconfig.h.top with the output from | |
23 | libguile/gen-scmconfig. gen-scmconfig bases its output on the | |
24 | information in the private config.h header, the contents of | |
25 | gen-scmconfig.h (which is created by configure.in from | |
26 | gen-scmconfig.h.in), and the information provided in this file, | |
27 | gen-scmconfig.c. | |
28 | ||
29 | libguile/__scm.h: Guile's public core header. This file is | |
30 | installed and publically visible. It includes | |
31 | libguile/scmconfig.h, the public config header and provides a | |
32 | place to make decisions based on the information gathered in | |
33 | scmconfig.h to define things that other headers can depend on. | |
34 | ||
35 | Notes and guidelines: | |
36 | ||
37 | - in the code below, be *VERY* careful not to use or rely on any | |
38 | runtime-dynamic information below. For example, you cannot use | |
39 | sizeof (FOO), but must use static information like SIZEOF_BAR | |
40 | (from config.h) or SCM_SIZEOF_BAZ (from scmconfig.h). This is | |
41 | because the gcc that is compiling gen-scmconfig.c and/or the | |
42 | machine that is running gen-scmconfig may not be the same | |
43 | compiler and/or hardware that will eventually be running Guile. | |
44 | (i.e. keep the cross-compilation case in mind). | |
45 | ||
46 | - try to avoid adding names to the public namespace when possible. | |
47 | Note in the code below, that in a number of cases, we detect a | |
48 | feature and based on that, we decide whether or not to print | |
49 | anything at all. This decreases the extraneous #defines and | |
50 | #ifdefery that we require in scmconfig.h | |
51 | ||
52 | - try to avoid adding any duplicate definitions to config.h and | |
53 | scmconfig.h. i.e. have just SCM_ENABLE_ELISP in scmconfig.h | |
54 | rather than ENABLE_ELISP in config.h and SCM_ENABLE_ELISP in | |
55 | scmconfig.h. | |
56 | ||
57 | - in cases where you need to communicate information from | |
58 | configure.in to gen-scmconfig.c, don't add an AC_DEFINE unless | |
59 | you need it for other purposes. Just add a suitable SCM_I_GSC_* | |
60 | variable to configure.in, set the value, AC_SUBST the value, and | |
61 | add an appropriate line to gen-scmconfig.h.in. All gen-scmconfig | |
62 | related AC_SUBST vars should be prefixed with SCM_I_GSC_. | |
63 | ||
64 | - make sure that anything that we explicitly typedef publically is | |
65 | prefixed with scm_t_. i.e. we used to typedef long to ptrdiff_t | |
66 | if we didn't detect ptrdiff_t, but this has been changed so that | |
67 | we typedef scm_t_ptrdiff instead so that we won't conflict with | |
68 | any non-guile header definitions of the same type. For types | |
69 | like intptr_t and uintptr_t which we just try to detect and don't | |
70 | actually define, it's fine not to have a corresponding scm_t_ | |
71 | type. | |
72 | ||
73 | - we now use SCM_SIZEOF_FOO != 0 rather than SCM_HAVE_FOO for any | |
74 | cases where the size might actually vary. For types where the | |
75 | size is fixed, we use SCM_HAVE_FOO, i.e. you can see us define or | |
76 | not define SCM_HAVE_T_INT64 below when appropriate. | |
77 | ||
78 | Rationales (not finished): | |
79 | ||
80 | Why do we use a C program here rather than AC_OUTPUT_COMMANDS? | |
81 | -------------------------------------------------------------- | |
82 | ||
83 | The main reason is that there are some values we would need | |
84 | access to at AC_OUTPUT_COMMANDs that are determined by configure | |
85 | but are not available at AC_OUTPUT time. The values are *only* | |
86 | available via config.h. We use gen-scmconfig so we can see those | |
87 | values and make decisions based on their settings. | |
88 | ||
89 | Why have gen-scmconfig.h.in? | |
90 | ---------------------------- | |
91 | ||
92 | Without that header, we could end up needing multiple aliases for | |
93 | public settings like SCM_ENABLE_ELISP. We can't define | |
94 | SCM_ENABLE_ELISP in config.h since that header is private and any | |
95 | definition in scmconfig.h would conflict (#ifndef might be | |
96 | possible but runs the risk of conflicting directives), so a | |
97 | likely solution would be to AC_DEFINE([SCM_I_ENABLE_ELISP]), and | |
98 | then use SCM_I_ENABLE_ELISP in gen-scmconfig via config.h to | |
99 | determine whether or not to #define SCM_ENABLE_ELISP, but this | |
100 | leaves us with two #defined symbols for each public setting -- | |
101 | better to just have one value (public or private) that all code | |
102 | uses. | |
103 | ||
104 | Having this header means we can AC_SUBST a value like | |
105 | SCM_I_GSC_ENABLE_ELISP and then set it in here via AC_OUTPUT | |
106 | substitutions, and gen-scmconfig can use that definition to | |
107 | determine whether or not to #define SCM_ENABLE_ELISP when | |
108 | generating scmconfig.h, and we end up with nothing extraneous | |
109 | added to config.h. | |
110 | ||
111 | **********************************************************************/ | |
112 | ||
113 | #if HAVE_CONFIG_H | |
114 | # include <config.h> | |
115 | #endif | |
116 | ||
117 | #include "gen-scmconfig.h" | |
118 | ||
119 | #include <stdio.h> | |
120 | #include <string.h> | |
121 | ||
122 | #define pf printf | |
123 | ||
124 | int | |
125 | main (int argc, char *argv[]) | |
126 | { | |
127 | pf ("/* This file is automatically generated --" | |
128 | " see configure.in for details */\n" | |
129 | "\n" | |
130 | "#ifndef SCM_SCMCONFIG_H\n" | |
131 | "#define SCM_SCMCONFIG_H\n"); | |
132 | ||
133 | /*** various important headers ***/ | |
134 | pf ("\n"); | |
135 | pf ("/* Important headers */\n"); | |
136 | if (SCM_I_GSC_NEEDS_STDINT_H) | |
137 | pf ("#include <stdint.h>\n"); | |
138 | if (SCM_I_GSC_NEEDS_INTTYPES_H) | |
139 | pf ("#include <inttypes.h>\n"); | |
140 | ||
141 | #ifdef HAVE_LIMITS_H | |
142 | pf ("#include <limits.h>\n"); | |
143 | #else | |
144 | pf ("/* limits.h not available */\n"); | |
145 | #endif | |
146 | ||
147 | # ifdef TIME_WITH_SYS_TIME | |
148 | pf ("#include <sys/time.h>\n"); | |
149 | pf ("#include <time.h>\n"); | |
150 | # else | |
151 | # ifdef HAVE_SYS_TIME_H | |
152 | pf ("#include <sys/time.h>\n"); | |
153 | # else | |
154 | # ifdef HAVE_TIME_H | |
155 | pf ("#include <time.h>\n"); | |
156 | # endif | |
157 | # endif | |
158 | # endif | |
159 | ||
160 | pf("\n"); | |
161 | #ifdef STDC_HEADERS | |
162 | pf ("#define SCM_HAVE_STDC_HEADERS 1 /* defined or undefined */\n"); | |
163 | pf ("#include <stdlib.h>\n"); | |
164 | # if HAVE_SYS_TYPES_H | |
165 | pf ("#include <sys/types.h>\n"); | |
166 | # endif | |
167 | # if HAVE_SYS_STDTYPES_H | |
168 | pf ("#include <sys/stdtypes.h>\n"); | |
169 | # endif | |
170 | pf ("#include <stddef.h>\n"); | |
171 | #else /* STDC_HEADERS */ | |
172 | pf ("/* #undef SCM_HAVE_STDC_HEADERS */"); | |
173 | #endif /* def STDC_HEADERS */ | |
174 | ||
175 | pf("\n"); | |
176 | #ifdef HAVE_SYS_SELECT_H | |
177 | pf ("#define SCM_HAVE_SYS_SELECT_H 1 /* defined or undefined */\n"); | |
178 | #else | |
179 | pf ("/* #undef SCM_HAVE_SYS_SELECT_H */\n"); | |
180 | #endif | |
181 | ||
182 | #ifdef HAVE_FLOATINGPOINT_H | |
183 | pf ("#define SCM_HAVE_FLOATINGPOINT_H 1 /* defined or undefined */\n"); | |
184 | #else | |
185 | pf ("/* #undef SCM_HAVE_FLOATINGPOINT_H */\n"); | |
186 | #endif | |
187 | ||
188 | #ifdef HAVE_IEEEFP_H | |
189 | pf ("#define SCM_HAVE_IEEEFP_H 1 /* defined or undefined */\n"); | |
190 | #else | |
191 | pf ("/* #undef SCM_HAVE_IEEEFP_H */\n"); | |
192 | #endif | |
193 | ||
194 | #ifdef HAVE_NAN_H | |
195 | pf ("#define SCM_HAVE_NAN_H 1 /* defined or undefined */\n"); | |
196 | #else | |
197 | pf ("/* #undef SCM_HAVE_NAN_H */\n"); | |
198 | #endif | |
199 | ||
200 | #ifdef HAVE_WINSOCK2_H | |
201 | pf ("#define SCM_HAVE_WINSOCK2_H 1 /* defined or undefined */\n"); | |
202 | #else | |
203 | pf ("/* #undef SCM_HAVE_WINSOCK2_H */\n"); | |
204 | #endif | |
205 | ||
206 | ||
207 | /*** GUILE_DEBUG (defined or undefined) ***/ | |
208 | pf ("\n"); | |
209 | pf ("/* Define to include various undocumented debugging functions. */\n"); | |
210 | if (SCM_I_GSC_GUILE_DEBUG) | |
211 | pf ("#define GUILE_DEBUG 1 /* defined or undefined */\n"); | |
212 | else | |
213 | pf ("/* #undef GUILE_DEBUG */\n"); | |
214 | ||
215 | /*** GUILE_DEBUG_FREELIST (defined or undefined) ***/ | |
216 | pf ("\n"); | |
217 | pf ("/* Define this to debug the free list (helps w/ GC bugs). */\n"); | |
218 | if (SCM_I_GSC_GUILE_DEBUG_FREELIST) | |
219 | pf ("#define GUILE_DEBUG_FREELIST 1 /* defined or undefined */\n"); | |
220 | else | |
221 | pf ("/* #undef GUILE_DEBUG_FREELIST */\n"); | |
222 | ||
223 | /*** SCM_ENABLE_DEPRECATED (0 or 1) ***/ | |
224 | pf ("\n"); | |
225 | pf ("/* Set to 1 if you want to enable deprecated features. */\n"); | |
226 | pf ("/* (value will be 0 or 1). */\n"); | |
227 | pf ("#define SCM_ENABLE_DEPRECATED %d\n", SCM_I_GSC_ENABLE_DEPRECATED); | |
228 | ||
229 | /*** SCM_ENABLE_ELISP (defined or undefined) ***/ | |
230 | pf ("\n"); | |
231 | pf ("/* Define this for Elisp support (in addition to Scheme). */\n"); | |
232 | if (SCM_I_GSC_ENABLE_ELISP) | |
233 | pf ("#define SCM_ENABLE_ELISP 1 /* defined or undefined */\n"); | |
234 | else | |
235 | pf ("/* #undef SCM_ENABLE_ELISP */\n"); | |
236 | ||
237 | /*** SCM_HAVE_ARRAYS (defined or undefined) ***/ | |
238 | pf ("\n"); | |
239 | pf ("/* Define this to add support for arrays and uniform arrays. */\n"); | |
240 | if (SCM_I_GSC_HAVE_ARRAYS) | |
241 | pf ("#define SCM_HAVE_ARRAYS 1 /* defined or undefined */\n"); | |
242 | else | |
243 | pf ("/* #undef SCM_HAVE_ARRAYS */\n"); | |
244 | ||
245 | /*** SCM_STACK_GROWS_UP (defined or undefined) ***/ | |
246 | pf ("\n"); | |
247 | pf ("/* Define this to add support for arrays and uniform arrays. */\n"); | |
248 | if (SCM_I_GSC_STACK_GROWS_UP) | |
249 | pf ("#define SCM_STACK_GROWS_UP 1 /* defined or undefined */\n"); | |
250 | else | |
251 | pf ("/* #undef SCM_STACK_GROWS_UP */\n"); | |
252 | ||
253 | /*** SCM_C_INLINE (defined to appropriate string or undefined) ***/ | |
254 | pf ("\n"); | |
255 | pf ("/* C compiler's syntax for inline functions if any,\n" | |
256 | " otherwise undefined. */\n"); | |
257 | if (SCM_I_GSC_C_INLINE) | |
258 | pf ("#define SCM_C_INLINE %s\n", SCM_I_GSC_C_INLINE); | |
259 | else | |
260 | pf ("/* #undef SCM_C_INLINE */\n"); | |
261 | ||
262 | pf ("\n"); | |
263 | pf ("/* Standard types. */\n"); | |
264 | ||
265 | pf ("/* These are always defined */\n"); | |
266 | pf ("#define SCM_SIZEOF_CHAR %d\n", SIZEOF_CHAR); | |
267 | pf ("#define SCM_SIZEOF_UNSIGNED_CHAR %d\n", SIZEOF_UNSIGNED_CHAR); | |
268 | pf ("#define SCM_SIZEOF_SHORT %d\n", SIZEOF_SHORT); | |
269 | pf ("#define SCM_SIZEOF_UNSIGNED_SHORT %d\n", SIZEOF_UNSIGNED_SHORT); | |
270 | pf ("#define SCM_SIZEOF_LONG %d\n", SIZEOF_LONG); | |
271 | pf ("#define SCM_SIZEOF_UNSIGNED_LONG %d\n", SIZEOF_UNSIGNED_LONG); | |
272 | pf ("#define SCM_SIZEOF_INT %d\n", SIZEOF_INT); | |
273 | pf ("#define SCM_SIZEOF_UNSIGNED_INT %d\n", SIZEOF_UNSIGNED_INT); | |
274 | ||
275 | pf ("\n"); | |
276 | pf ("/* Size of (unsigned) long long or 0 if not available (scm_t_*64 may\n" | |
277 | " be more likely to be what you want */\n"); | |
278 | pf ("#define SCM_SIZEOF_LONG_LONG %d\n", SIZEOF_LONG_LONG); | |
279 | pf ("#define SCM_SIZEOF_UNSIGNED_LONG_LONG %d\n", SIZEOF_UNSIGNED_LONG_LONG); | |
280 | ||
281 | pf ("\n"); | |
282 | pf ("/* These are always defined. */\n"); | |
283 | pf ("typedef %s scm_t_int8;\n", SCM_I_GSC_T_INT8); | |
284 | pf ("typedef %s scm_t_uint8;\n", SCM_I_GSC_T_UINT8); | |
285 | pf ("typedef %s scm_t_int16;\n", SCM_I_GSC_T_INT16); | |
286 | pf ("typedef %s scm_t_uint16;\n", SCM_I_GSC_T_UINT16); | |
287 | pf ("typedef %s scm_t_int32;\n", SCM_I_GSC_T_INT32); | |
288 | pf ("typedef %s scm_t_uint32;\n", SCM_I_GSC_T_UINT32); | |
289 | ||
290 | pf ("\n"); | |
291 | pf ("/* 64-bit integer -- if available SCM_T_INT64 will be defined and\n" | |
292 | " scm_t_int64 will be a suitable type. */\n"); | |
293 | if (SCM_I_GSC_T_INT64) | |
294 | { | |
295 | pf ("#define SCM_HAVE_T_INT64 1\n"); | |
296 | pf ("typedef %s scm_t_int64;\n", SCM_I_GSC_T_INT64); | |
297 | } | |
298 | else | |
299 | pf ("/* #undef SCM_HAVE_T_INT64 */\n"); | |
300 | ||
301 | pf ("\n"); | |
302 | pf ("/* 64-bit unsigned integer -- if available SCM_T_INT64 will be\n" | |
303 | " defined and scm_t_uint64 will be a suitable type. */\n"); | |
304 | if (SCM_I_GSC_T_UINT64) | |
305 | { | |
306 | pf ("#define SCM_HAVE_T_UINT64 1\n"); | |
307 | pf ("typedef %s scm_t_uint64;\n", SCM_I_GSC_T_UINT64); | |
308 | } | |
309 | else | |
310 | pf ("/* #undef SCM_HAVE_T_UINT64 */\n"); | |
311 | ||
312 | pf ("\n"); | |
313 | pf ("/* scm_t_ptrdiff_t and size, always defined -- defined to long if\n" | |
314 | " platform doesn't have ptrdiff_t. */\n"); | |
315 | pf ("typedef %s scm_t_ptrdiff;\n", SCM_I_GSC_T_PTRDIFF); | |
316 | if (0 == strcmp ("long", SCM_I_GSC_T_PTRDIFF)) | |
317 | pf ("#define SCM_SIZEOF_SCM_T_PTRDIFF %d\n", SIZEOF_LONG); | |
318 | else | |
319 | pf ("#define SCM_SIZEOF_SCM_T_PTRDIFF %d\n", SIZEOF_PTRDIFF_T); | |
320 | ||
321 | pf ("\n"); | |
322 | pf ("/* Size of intptr_t or 0 if not available */\n"); | |
323 | pf ("#define SCM_SIZEOF_INTPTR_T %d\n", SIZEOF_INTPTR_T); | |
324 | pf ("/* Size of uintptr_t or 0 if not available */\n"); | |
325 | pf ("#define SCM_SIZEOF_UINTPTR_T %d\n", SIZEOF_UINTPTR_T); | |
326 | ||
327 | pf ("\n"); | |
328 | pf ("/* same as POSIX \"struct timespec\" -- always defined */\n"); | |
329 | #ifdef HAVE_STRUCT_TIMESPEC | |
330 | pf ("typedef struct timespec scm_t_timespec;\n"); | |
331 | #else | |
332 | pf ("/* POSIX.4 structure for a time value. This is like a `struct timeval'" | |
333 | " but has nanoseconds instead of microseconds. */\n"); | |
334 | pf ("typedef struct\n" | |
335 | "{\n" | |
336 | " long int tv_sec; /* Seconds. */\n" | |
337 | " long int tv_nsec; /* Nanoseconds. */\n" | |
338 | "} scm_t_timespec;\n"); | |
339 | #endif | |
340 | ||
341 | pf ("\n"); | |
342 | pf ("/*** Threading model (scmconfig.h support not finished) ***/\n"); | |
343 | ||
344 | pf ("/* Define if using pthread multithreading. */\n"); | |
345 | if (SCM_I_GSC_USE_PTHREAD_THREADS) | |
346 | pf ("#define SCM_USE_PTHREAD_THREADS 1 /* defined or undefined */\n"); | |
347 | else | |
348 | pf ("/* #undef SCM_USE_PTHREAD_THREADS */\n"); | |
349 | ||
350 | pf ("/* Define if using one-thread 'multi'threading. */\n"); | |
351 | if (SCM_I_GSC_USE_NULL_THREADS) | |
352 | pf ("#define SCM_USE_NULL_THREADS 1 /* defined or undefined */\n"); | |
353 | else | |
354 | pf ("/* #undef SCM_USE_NULL_THREADS */\n"); | |
355 | ||
356 | pf ("/* FIXME: what is this used for now? */\n"); | |
357 | if (SCM_I_GSC_USE_COOP_THREADS) | |
358 | pf ("#define SCM_USE_COOP_THREADS 1 /* defined or undefined */\n"); | |
359 | else | |
360 | pf ("/* #undef SCM_USE_COOP_THREADS */\n"); | |
361 | ||
362 | #if USE_DLL_IMPORT | |
363 | pf ("\n"); | |
364 | pf ("/* Define some additional CPP macros on Win32 platforms. */\n"); | |
365 | pf ("# define __REGEX_IMPORT__ 1\n"); | |
366 | pf ("# define __CRYPT_IMPORT__ 1\n"); | |
367 | pf ("# define __READLINE_IMPORT__ 1\n"); | |
368 | pf ("# define QT_IMPORT 1\n"); | |
369 | #endif | |
370 | ||
371 | pf ("\n"); | |
372 | pf ("#if SCM_ENABLE_DEPRECATED == 1\n" | |
373 | "# define USE_THREADS 1 /* always true now */\n" | |
374 | "# define GUILE_ISELECT 1 /* always true now */\n" | |
375 | "# define READER_EXTENSIONS 1 /* always true now */\n" | |
376 | "# define DEBUG_EXTENSIONS 1 /* always true now */\n" | |
377 | "# define DYNAMIC_LINKING 1 /* always true now */\n" | |
378 | "#endif\n"); | |
379 | printf ("\n"); | |
380 | ||
381 | printf ("#endif\n"); | |
382 | ||
383 | return 0; | |
384 | } |