[patch] load wininet dynamically in cygcheck

2006-01-13 Thread Brian Dessent

This uses LoadLibrary and GetProcAddress instead of -lwininet so that systems
lacking IE3 can still run cygcheck.  Tested on XP and NT4, and verified that
with WININET.DLL renamed cygcheck can still function.

2006-01-13  Brian Dessent  <[EMAIL PROTECTED]>

* Makefile.in (cygcheck.exe): Do not link against libwininet.a.
* cygcheck.cc (pInternetCloseHandle): Define global function pointer.
(display_internet_error): Use it.
(package_grep): Attempt to load wininet.dll at runtime.  Call WinInet
API through function pointers throughout.

BrianIndex: Makefile.in
===
RCS file: /cvs/src/src/winsup/utils/Makefile.in,v
retrieving revision 1.58
diff -u -p -r1.58 Makefile.in
--- Makefile.in 22 Nov 2005 17:19:17 -  1.58
+++ Makefile.in 13 Jan 2006 18:39:16 -
@@ -99,15 +99,15 @@ else
$(CXX) $(MINGW_CXXFLAGS) -o $@ ${wordlist 1,2,$^} -B$(mingw_build)/ 
$(MINGW_LDFLAGS)
 endif
 
-cygcheck.exe: cygcheck.o path.o dump_setup.o $(MINGW_DEP_LDLIBS) 
$(w32api_lib)/libwininet.a
+cygcheck.exe: cygcheck.o path.o dump_setup.o $(MINGW_DEP_LDLIBS)
 ifeq "$(libz)" ""
@echo '*** Building cygcheck without package content checking due to 
missing mingw libz.a.'
 endif
 ifdef VERBOSE
-   $(CXX) $(MINGW_CXXFLAGS) -o $@ ${wordlist 1,3,$^} -B$(mingw_build)/ 
$(MINGW_LDFLAGS) $(libz) $(w32api_lib)/libwininet.a
+   $(CXX) $(MINGW_CXXFLAGS) -o $@ ${wordlist 1,3,$^} -B$(mingw_build)/ 
$(MINGW_LDFLAGS) $(libz)
 else
-   @echo $(CXX) -o $@ ${wordlist 1,3,$^} ${filter-out -B%, 
$(MINGW_CXXFLAGS) $(MINGW_LDFLAGS)} $(libz) $(w32api_lib)/libwininet.a;\
-   $(CXX) $(MINGW_CXXFLAGS) -o $@ ${wordlist 1,3,$^} -B$(mingw_build)/ 
$(MINGW_LDFLAGS) $(libz) $(w32api_lib)/libwininet.a
+   @echo $(CXX) -o $@ ${wordlist 1,3,$^} ${filter-out -B%, 
$(MINGW_CXXFLAGS) $(MINGW_LDFLAGS)} $(libz);\
+   $(CXX) $(MINGW_CXXFLAGS) -o $@ ${wordlist 1,3,$^} -B$(mingw_build)/ 
$(MINGW_LDFLAGS) $(libz)
 endif
 
 dumper.o: dumper.cc dumper.h
Index: cygcheck.cc
===
RCS file: /cvs/src/src/winsup/utils/cygcheck.cc,v
retrieving revision 1.83
diff -u -p -r1.83 cygcheck.cc
--- cygcheck.cc 13 Jan 2006 13:39:05 -  1.83
+++ cygcheck.cc 13 Jan 2006 18:39:16 -
@@ -37,6 +37,10 @@ int find_package = 0;
 int list_package = 0;
 int grep_packages = 0;
 
+/* This is global because it's used in both internet_display_error as well
+   as package_grep.  */
+BOOL (WINAPI *pInternetCloseHandle) (HINTERNET);
+
 #ifdef __GNUC__
 typedef long long longlong;
 #else
@@ -161,7 +165,7 @@ display_internet_error (const char *mess
 
   va_start (hptr, message);
   while ((h = va_arg (hptr, HINTERNET)) != 0)
-InternetCloseHandle (h);
+pInternetCloseHandle (h);
   va_end (hptr);
 
   return 1;
@@ -1588,6 +1592,43 @@ package_grep (char *search)
 {
   char buf[1024];
 
+  /* Attempt to dynamically load the necessary WinInet API functions so that
+ cygcheck can still function on older systems without IE.  */
+  HMODULE hWinInet;
+  if (!(hWinInet = LoadLibrary ("wininet.dll")))
+{
+  fputs ("Unable to locate WININET.DLL.  This feature requires Microsoft "
+ "Internet Explorer v3 or later to function.\n", stderr);
+  return 1;
+}
+
+  /* InternetCloseHandle is used outside this function so it is declared
+ global.  The rest of these functions are only used here, so declare them
+ and call GetProcAddress for each of them with the following macro.  */
+
+  pInternetCloseHandle = (BOOL (WINAPI *) (HINTERNET))
+GetProcAddress (hWinInet, "InternetCloseHandle");
+#define make_func_pointer(name, ret, args) ret (WINAPI * p##name) args = \
+(ret (WINAPI *) args) GetProcAddress (hWinInet, #name);
+  make_func_pointer (InternetAttemptConnect, DWORD, (DWORD));
+  make_func_pointer (InternetOpenA, HINTERNET, (LPCSTR, DWORD, LPCSTR, LPCSTR, 
+DWORD));
+  make_func_pointer (InternetOpenUrlA, HINTERNET, (HINTERNET, LPCSTR, LPCSTR, 
+   DWORD, DWORD, DWORD));
+  make_func_pointer (InternetReadFile, BOOL, (HINTERNET, PVOID, DWORD, 
PDWORD));
+  make_func_pointer (HttpQueryInfoA, BOOL, (HINTERNET, DWORD, PVOID, PDWORD,
+PDWORD));
+#undef make_func_pointer
+
+  if(!pInternetCloseHandle || !pInternetAttemptConnect || !pInternetOpenA
+ || !pInternetOpenUrlA || !pInternetReadFile || !pHttpQueryInfoA)
+{
+  fputs ("Unable to load one or more functions from WININET.DLL.  This "
+ "feature requires Microsoft Internet Explorer v3 or later to "
+ "function.\n", stderr);
+  return 1;
+}
+
   /* construct the actual URL by escaping  */
   char *url = (char *) alloca (sizeof (base_url) + strlen (search) * 3);
   strcpy (url, base_url);
@@ -1610,7 +165

Re: [patch] load wininet dynamically in cygcheck

2006-01-15 Thread Corinna Vinschen
On Jan 13 10:49, Brian Dessent wrote:
> 
> This uses LoadLibrary and GetProcAddress instead of -lwininet so that systems
> lacking IE3 can still run cygcheck.  Tested on XP and NT4, and verified that
> with WININET.DLL renamed cygcheck can still function.
> 
> 2006-01-13  Brian Dessent  <[EMAIL PROTECTED]>
> 
>   * Makefile.in (cygcheck.exe): Do not link against libwininet.a.
>   * cygcheck.cc (pInternetCloseHandle): Define global function pointer.
>   (display_internet_error): Use it.
>   (package_grep): Attempt to load wininet.dll at runtime.  Call WinInet
>   API through function pointers throughout.

I tested it additionally on my NT4 which never had IE3 installed and it
works fine, as on XP and 2K3-WOW64.

Thanks, applied.


Corinna


-- 
Corinna Vinschen  Please, send mails regarding Cygwin to
Cygwin Project Co-Leader  cygwin AT cygwin DOT com
Red Hat