build: Rework mmap checks

Switch to AC_CHECK_DECLS/check_symbol_exists. Don't check for
sys/mman.h separately. Don't check for munmap.

CMakeLists.txt

@@ -144,14 +144,12 @@ check_include_files(dl.h HAVE_DL_H)
 check_symbol_exists(getentropy "sys/random.h" HAVE_DECL_GETENTROPY)
 check_library_exists(history append_history "" HAVE_LIBHISTORY)
 check_library_exists(readline readline "" HAVE_LIBREADLINE)
-check_function_exists(mmap HAVE_MMAP)
-check_function_exists(munmap HAVE_MUNMAP)
+check_symbol_exists(mmap "sys/mman.h" HAVE_DECL_MMAP)
 check_include_files(netdb.h HAVE_NETDB_H)
 check_include_files(netinet/in.h HAVE_NETINET_IN_H)
 check_include_files(poll.h HAVE_POLL_H)
 check_library_exists(dld shl_load "" HAVE_SHLLOAD)
 check_include_files(stdint.h HAVE_STDINT_H)
-check_include_files(sys/mman.h HAVE_SYS_MMAN_H)
 check_include_files(sys/select.h HAVE_SYS_SELECT_H)
 check_include_files(sys/socket.h HAVE_SYS_SOCKET_H)
 

config.h.cmake.in

@@ -23,15 +23,7 @@
 #cmakedefine HAVE_LIBREADLINE 1
 
 /* Define to 1 if you have the `mmap' function. */
-#cmakedefine HAVE_MMAP 1
-
-/* Define to 1 if you have the `munmap' function. */
-#cmakedefine HAVE_MUNMAP 1
-
-/* mmap() is no good without munmap() */
-#if defined(HAVE_MMAP) && !defined(HAVE_MUNMAP)
-#  undef /**/ HAVE_MMAP
-#endif
+#cmakedefine HAVE_DECL_MMAP 1
 
 /* Define to 1 if you have the <netdb.h> header file. */
 #cmakedefine HAVE_NETDB_H 1
@@ -51,9 +43,6 @@
 /* Define to 1 if you have the <stdint.h> header file. */
 #cmakedefine HAVE_STDINT_H 1
 
-/* Define to 1 if you have the <sys/mman.h> header file. */
-#cmakedefine HAVE_SYS_MMAN_H 1
-
 /* Define to 1 if you have the <sys/select.h> header file. */
 #cmakedefine HAVE_SYS_SELECT_H 1
 

configure.ac

@@ -298,20 +298,12 @@ dnl
 dnl Checks for header files.
 dnl
 AC_CHECK_HEADERS([stdint.h])
-AC_CHECK_HEADERS([sys/mman.h])
 AC_CHECK_HEADERS([dl.h dlfcn.h])
 AC_CHECK_HEADERS([glob.h])
 AM_CONDITIONAL(WITH_GLOB, test "$ac_cv_header_glob_h" = "yes")
 
 dnl Checks for library functions.
-
-AC_CHECK_FUNCS([mmap munmap])
-
-AH_VERBATIM([HAVE_MUNMAP_AFTER],[/* mmap() is no good without munmap() */
-#if defined(HAVE_MMAP) && !defined(HAVE_MUNMAP)
-#  undef /**/ HAVE_MMAP
-#endif])
-
+AC_CHECK_DECLS([mmap], [], [], [#include <sys/mman.h>])
 AC_CHECK_DECLS([getentropy], [], [], [#include <sys/random.h>])
 
 dnl

meson.build

@@ -234,7 +234,6 @@ config_h.set_quoted('LOCALEDIR', dir_locale)
 # header files
 xml_check_headers = [
     'stdint.h',
-    'sys/mman.h',
     'dl.h',
     'dlfcn.h',
     'glob.h',
@@ -258,8 +257,7 @@ endforeach
 xml_check_functions = [
     # fct             | header
     ['getentropy', 'sys/random.h', 'HAVE_DECL_GETENTROPY'],
-    ['mmap', 'sys/mman.h', 'HAVE_MMAP'],
-    ['munmap', 'sys/mman.h', 'HAVE_MUNMAP'],
+    ['mmap', 'sys/mman.h', 'HAVE_DECL_MMAP'],
 ]
 
 foreach function : xml_check_functions

xmllint.c

@@ -28,7 +28,7 @@
   #include <unistd.h>
 #endif
 
-#ifdef HAVE_SYS_MMAN_H
+#if HAVE_DECL_MMAP
   #include <sys/mman.h>
   /* seems needed for Solaris */
   #ifndef MAP_FAILED
@@ -140,7 +140,7 @@ static int htmlout = 0;
 static int push = 0;
 static int pushsize = 4096;
 #endif /* LIBXML_PUSH_ENABLED */
-#ifdef HAVE_MMAP
+#if HAVE_DECL_MMAP
 static int memory = 0;
 #endif
 static int testIO = 0;
@@ -1481,7 +1481,7 @@ static void processNode(xmlTextReaderPtr reader) {
 static void streamFile(const char *filename) {
     xmlTextReaderPtr reader;
     int ret;
-#ifdef HAVE_MMAP
+#if HAVE_DECL_MMAP
     int fd = -1;
     struct stat info;
     const char *base = NULL;
@@ -1630,7 +1630,7 @@ static void streamFile(const char *filename) {
 	patstream = NULL;
     }
 #endif
-#ifdef HAVE_MMAP
+#if HAVE_DECL_MMAP
     if (memory) {
 	munmap((char *) base, info.st_size);
 	close(fd);
@@ -1906,7 +1906,7 @@ parseFile(const char *filename, xmlParserCtxtPtr rectxt) {
     }
 #endif /* LIBXML_PUSH_ENABLED */
 
-#ifdef HAVE_MMAP
+#if HAVE_DECL_MMAP
     if ((html) && (memory)) {
 	int fd;
 	struct stat info;
@@ -2028,7 +2028,7 @@ parseFile(const char *filename, xmlParserCtxtPtr rectxt) {
 
             doc = xmlCtxtReadIO(ctxt, myRead, myClose, f, filename, NULL,
                                 options);
-#ifdef HAVE_MMAP
+#if HAVE_DECL_MMAP
         } else if (memory) {
             int fd;
             struct stat info;
@@ -2304,7 +2304,7 @@ parseAndPrintFile(const char *filename, xmlParserCtxtPtr rectxt) {
 		}
 	    } else
 #endif
-#ifdef HAVE_MMAP
+#if HAVE_DECL_MMAP
 	    if (memory) {
 		xmlChar *result;
 		int len;
@@ -2332,7 +2332,7 @@ parseAndPrintFile(const char *filename, xmlParserCtxtPtr rectxt) {
 		}
 
 	    } else
-#endif /* HAVE_MMAP */
+#endif /* HAVE_DECL_MMAP */
 	    if (compress) {
 		xmlSaveFile(output ? output : "-", doc);
 	    } else {
@@ -2692,7 +2692,7 @@ static void usage(FILE *f, const char *name) {
     fprintf(f, "\t--push : use the push mode of the parser\n");
     fprintf(f, "\t--pushsmall : use the push mode of the parser using tiny increments\n");
 #endif /* LIBXML_PUSH_ENABLED */
-#ifdef HAVE_MMAP
+#if HAVE_DECL_MMAP
     fprintf(f, "\t--memory : parse from memory\n");
 #endif
     fprintf(f, "\t--maxmem nbbytes : limits memory allocation to nbbytes bytes\n");
@@ -2884,7 +2884,7 @@ xmllintMain(int argc, const char **argv, xmlResourceLoader loader) {
     push = 0;
     pushsize = 4096;
 #endif /* LIBXML_PUSH_ENABLED */
-#ifdef HAVE_MMAP
+#if HAVE_DECL_MMAP
     memory = 0;
 #endif
     testIO = 0;
@@ -3069,7 +3069,7 @@ xmllintMain(int argc, const char **argv, xmlResourceLoader loader) {
             pushsize = 10;
         }
 #endif /* LIBXML_PUSH_ENABLED */
-#ifdef HAVE_MMAP
+#if HAVE_DECL_MMAP
 	else if ((!strcmp(argv[i], "-memory")) ||
 	         (!strcmp(argv[i], "--memory")))
 	    memory++;