* Makefile.in (DLL_OFILES): Add hookapi.o. Eliminate some cruft.

* cygheap.h (cygheap_types): Add new enum: HEAP_1_HOOK.
(hook_chain): New struct.
(init_cygheap::hooks): Define new element.
* cygheap.cc (cygheap_fixup_in_child): Zero hook chain on exec.
* dcrt0.cc (dll_crt0_1): Call ld_preload just before calling main function.
* external.cc (cygwin_internal): Implement CW_HOOK.
* fork.cc (fork_child): Call fixup_hooks_after_fork.
* init.cc (cygwin_hmodule): Reinstate after a long absence.
* include/sys/cygwin.h: Define CW_HOOK.
* hookapi.cc: New file.
* select.cc (start_thread_socket): Add debugging output.
* fhandler_disk_file.cc (fhandler_disk_file::fchmod): gcc 4.x accommodation.
* fhandler_socket.cc (fhandler_socket::connect): Make sure that err is
initialized.

winsup/cygwin/ChangeLog

@@ -1,3 +1,25 @@
+2005-03-22  Christopher Faylor  <cgf@timesys.com>
+
+	* Makefile.in (DLL_OFILES): Add hookapi.o.  Eliminate some cruft.
+	* cygheap.h (cygheap_types): Add new enum: HEAP_1_HOOK.
+	(hook_chain): New struct.
+	(init_cygheap::hooks): Define new element.
+	* cygheap.cc (cygheap_fixup_in_child): Zero hook chain on exec.
+	* dcrt0.cc (dll_crt0_1): Call ld_preload just before calling main function.
+	* external.cc (cygwin_internal): Implement CW_HOOK.
+	* fork.cc (fork_child): Call fixup_hooks_after_fork.
+	* init.cc (cygwin_hmodule): Reinstate after a long absence.
+	* include/sys/cygwin.h: Define CW_HOOK.
+	* hookapi.cc: New file.
+
+	* select.cc (start_thread_socket): Add debugging output.
+
+	* fhandler_disk_file.cc (fhandler_disk_file::fchmod): gcc 4.x
+	accommodation.
+
+	* fhandler_socket.cc (fhandler_socket::connect): Make sure that err is
+	initialized.
+
 2005-03-22  Corinna Vinschen  <corinna@vinschen.de>
 
 	* cygwin.din (__ctype_ptr): Export.

winsup/cygwin/Makefile.in

@@ -117,7 +117,7 @@ MALLOC_OFILES=@MALLOC_OFILES@
 DLL_IMPORTS:=$(w32api_lib)/libkernel32.a $(w32api_lib)/libadvapi32.a
 
 MT_SAFE_OBJECTS:=
-# Please maintain this list in sorted order, with maximum files per 80 col line
+# Please maintain this list in sorted order, with maximum files per 85 col line
 #
 DLL_OFILES:=assert.o autoload.o bsdlib.o cxx.o cygheap.o cygthread.o cygtls.o \
 	dcrt0.o debug.o delqueue.o devices.o dir.o dlfcn.o dll_init.o dtable.o \
@@ -127,12 +127,12 @@ DLL_OFILES:=assert.o autoload.o bsdlib.o cxx.o cygheap.o cygthread.o cygtls.o \
 	fhandler_nodevice.o fhandler_proc.o fhandler_process.o \
 	fhandler_random.o fhandler_raw.o fhandler_registry.o fhandler_serial.o \
 	fhandler_socket.o fhandler_tape.o fhandler_termios.o \
-	fhandler_tty.o fhandler_virtual.o fhandler_windows.o \
+	fhandler_tty.o fhandler_virtual.o fhandler_windows.o fhandler_zero.o \
-	fhandler_zero.o flock.o fnmatch.o fork.o getopt.o glob.o grp.o heap.o \
+	flock.o fnmatch.o fork.o getopt.o glob.o grp.o heap.o hookapi.o \
 	init.o ioctl.o ipc.o iruserok.o localtime.o malloc_wrapper.o miscfuncs.o \
 	mmap.o msg.o net.o netdb.o ntea.o passwd.o path.o pinfo.o pipe.o \
-	poll.o pthread.o regcomp.o regerror.o regexec.o regfree.o registry.o \
+	poll.o pthread.o regcomp.o regerror.o regexec.o regfree.o \
-	resource.o scandir.o sched.o sec_acl.o sec_helper.o security.o \
+	registry.o resource.o scandir.o sched.o sec_acl.o sec_helper.o security.o \
 	select.o sem.o shared.o shm.o sigfe.o signal.o sigproc.o smallprint.o \
 	spawn.o strace.o strsep.o strsig.o sync.o syscalls.o sysconf.o \
 	syslog.o termios.o thread.o timer.o times.o tty.o uinfo.o uname.o \
@@ -254,6 +254,7 @@ grp_CFLAGS:=-fomit-frame-pointer
 malloc_CFLAGS:=-fomit-frame-pointer
 malloc_wrapper_CFLAGS:=-fomit-frame-pointer
 miscfuncs_CFLAGS:=-fomit-frame-pointer
+net_CFLAGS:=-fomit-frame-pointer
 passwd_CFLAGS:=-fomit-frame-pointer
 regcomp_CFLAGS=-fomit-frame-pointer
 regerror_CFLAGS=-fomit-frame-pointer
@@ -267,7 +268,7 @@ uinfo_CFLAGS:=-fomit-frame-pointer
 endif
 
 .PHONY: all force dll_ofiles install all_target install_target all_host install_host \
-	install install-libs install-headers -lgcc
+	install install-libs install-headers
 
 .SUFFIXES:
 .SUFFIXES: .c .cc .def .a .o .d .s
@@ -434,11 +435,6 @@ winver_stamp: mkvers.sh include/cygwin/version.h winver.rc $(DLL_OFILES)
 	$(COMPILE_CXX) -o version.o version.cc && \
 	touch $@
 
--lgcc:
-	:
-
-#
-
 Makefile: cygwin.din
 
 $(DEF_FILE): gendef cygwin.din $(srcdir)/tlsoffsets.h

winsup/cygwin/cygheap.cc

@@ -21,7 +21,6 @@
 #include "child_info.h"
 #include "heap.h"
 #include "sync.h"
-#include "shared_info.h"
 #include "sigproc.h"
 
 init_cygheap NO_COPY *cygheap;
@@ -185,6 +184,7 @@ cygheap_fixup_in_child (bool execed)
 
   if (execed)
     {
+      cygheap->hooks.next = NULL;
       cygheap->user_heap.base = NULL;		/* We can allocate the heap anywhere */
       /* Walk the allocated memory chain looking for orphaned memory from
 	 previous execs */

winsup/cygwin/cygheap.h

@@ -21,6 +21,7 @@ enum cygheap_types
   HEAP_ARCHETYPES,
   HEAP_TLS,
   HEAP_1_START,
+  HEAP_1_HOOK,
   HEAP_1_STR,
   HEAP_1_ARGV,
   HEAP_1_BUF,
@@ -262,6 +263,13 @@ struct user_heap_info
   unsigned chunk;
 };
 
+struct hook_chain
+{
+  void **loc;
+  const void *func;
+  struct hook_chain *next;
+};
+
 struct init_cygheap
 {
   _cmalloc_entry *chain;
@@ -291,6 +299,7 @@ struct init_cygheap
   int open_fhs;
   pid_t pid;			/* my pid */
   HANDLE pid_handle;		/* handle for my pid */
+  hook_chain hooks;
   void close_ctty ();
 };
 

winsup/cygwin/dcrt0.cc

@@ -41,6 +41,8 @@ details. */
 
 #define PREMAIN_LEN (sizeof (user_data->premain) / sizeof (user_data->premain[0]))
 
+void ld_preload ();
+
 HANDLE NO_COPY hMainProc = (HANDLE) -1;
 HANDLE NO_COPY hMainThread;
 
@@ -857,6 +859,7 @@ dll_crt0_1 (char *)
      do this for noncygwin case since the signal thread is blocked due to
      LoadLibrary serialization. */
   wait_for_sigthread ();
+  ld_preload ();
   if (user_data->main)
     exit (user_data->main (__argc, __argv, *user_data->envptr));
 }

winsup/cygwin/external.cc

@@ -28,6 +28,8 @@ details. */
 #include "pwdgrp.h"
 #include "cygtls.h"
 
+void *hook_cygwin (const char *, const void *);
+
 static external_pinfo *
 fillout_pinfo (pid_t pid, int winpid)
 {
@@ -298,6 +300,12 @@ cygwin_internal (cygwin_getinfo_types t, ...)
 	    }
 	  return p.binmode ();
 	}
+      case CW_HOOK:
+	{
+	  const char *name = va_arg (arg, const char *);
+	  const void *hookfn = va_arg (arg, const void *);
+	  return (unsigned long) hook_cygwin (name, hookfn);
+	}
       default:
 	return (DWORD) -1;
     }

winsup/cygwin/fhandler_disk_file.cc

@@ -429,9 +429,9 @@ fhandler_disk_file::fchmod (mode_t mode)
 
   /* if the mode we want has any write bits set, we can't be read only. */
   if (mode & (S_IWUSR | S_IWGRP | S_IWOTH))
-    (DWORD) pc &= ~FILE_ATTRIBUTE_READONLY;
+    pc &= (DWORD) ~FILE_ATTRIBUTE_READONLY;
   else
-    (DWORD) pc |= FILE_ATTRIBUTE_READONLY;
+    pc |= (DWORD) FILE_ATTRIBUTE_READONLY;
 
   if (!SetFileAttributes (pc, pc))
     __seterrno ();

winsup/cygwin/fhandler_socket.cc

@@ -698,7 +698,9 @@ fhandler_socket::connect (const struct sockaddr *name, int namelen)
 
   res = ::connect (get_socket (), (sockaddr *) &sin, namelen);
 
-  if (res)
+  if (!res)
+    err = 0;
+  else
     {
       err = WSAGetLastError ();
       /* Special handling for connect to return the correct error code

winsup/cygwin/fork.cc

@@ -154,6 +154,7 @@ sync_with_parent (const char *s, bool hang_self)
 static int __stdcall
 fork_child (HANDLE& hParent, dll *&first_dll, bool& load_dlls)
 {
+  extern void fixup_hooks_after_fork ();
   extern void fixup_timers_after_fork ();
   debug_printf ("child is running.  pid %d, ppid %d, stack here %p",
 		myself->pid, myself->ppid, __builtin_frame_address (0));
@@ -232,6 +233,7 @@ fork_child (HANDLE& hParent, dll *&first_dll, bool& load_dlls)
 
   pthread::atforkchild ();
   fixup_timers_after_fork ();
+  fixup_hooks_after_fork ();
   cygbench ("fork-child");
   cygwin_finished_initializing = true;
   return 0;

winsup/cygwin/hookapi.cc

@@ -0,0 +1,218 @@
+#include "winsup.h"
+#include "cygerrno.h"
+#include "security.h"
+#include "path.h"
+#include "fhandler.h"
+#include "dtable.h"
+#include "cygheap.h"
+#include <stdlib.h>
+#include <imagehlp.h>
+#include <alloca.h>
+
+#define rva(coerce, base, addr) (coerce) ((char *) (base) + (addr))
+#define rvacyg(coerce, addr) rva (coerce, cygwin_hmodule, addr)
+
+struct function_hook
+{
+  const char *name;	// Function name, e.g. "DirectDrawCreateEx".
+  const void *hookfn;	// Address of your function.
+  void *origfn;		// Stored by HookAPICalls, the address of the original function.
+};
+
+/* Given an HMODULE, returns a pointer to the PE header */
+static PIMAGE_NT_HEADERS
+PEHeaderFromHModule (HMODULE hModule)
+{
+  PIMAGE_NT_HEADERS pNTHeader = NULL;
+
+  if (PIMAGE_DOS_HEADER(hModule) ->e_magic != IMAGE_DOS_SIGNATURE)
+    /* nothing */;
+  else
+    {
+      pNTHeader = PIMAGE_NT_HEADERS (PBYTE (hModule)
+				     + PIMAGE_DOS_HEADER (hModule) ->e_lfanew);
+      if (pNTHeader->Signature != IMAGE_NT_SIGNATURE)
+	pNTHeader = NULL;
+    }
+
+  return pNTHeader;
+}
+
+void *
+putmem (PIMAGE_THUNK_DATA pi, const void *hookfn)
+{
+
+  DWORD flOldProtect, flNewProtect, flDontCare;
+  MEMORY_BASIC_INFORMATION mbi;
+
+  /* Get the current protection attributes */
+  VirtualQuery (pi, &mbi, sizeof (mbi));
+
+  /* Remove ReadOnly and ExecuteRead attributes, add on ReadWrite flag */
+  flNewProtect = mbi.Protect;
+  flNewProtect &= ~(PAGE_READONLY | PAGE_EXECUTE_READ);
+  flNewProtect |= PAGE_READWRITE;
+
+  if (!VirtualProtect (pi, sizeof (PVOID), flNewProtect, &flOldProtect) )
+    return NULL;
+
+  void *origfn = (void *) pi->u1.Function;
+  pi->u1.Function = (DWORD) hookfn;
+
+  (void) VirtualProtect (pi, sizeof (PVOID), flOldProtect, &flDontCare);
+  return origfn;
+}
+
+/* Builds stubs for and redirects the IAT for one DLL (pImportDesc) */
+
+static bool
+RedirectIAT (function_hook& fh, PIMAGE_IMPORT_DESCRIPTOR pImportDesc,
+	     HMODULE hm)
+{
+  // If no import names table, we can't redirect this, so bail
+  if (pImportDesc->OriginalFirstThunk == 0)
+      return false;
+
+  /* import address table */
+  PIMAGE_THUNK_DATA pt = rva (PIMAGE_THUNK_DATA, hm, pImportDesc->FirstThunk);
+  /* import names table */
+  PIMAGE_THUNK_DATA pn = rva (PIMAGE_THUNK_DATA, hm, pImportDesc->OriginalFirstThunk);
+
+  /* Scan through the IAT, completing the stubs and redirecting the IAT
+     entries to point to the stubs. */
+  for (PIMAGE_THUNK_DATA pi = pt; pn->u1.Ordinal; pi++, pn++)
+    {
+      if (IMAGE_SNAP_BY_ORDINAL (pn->u1.Ordinal) )
+	continue;
+
+      /* import by name */
+      PIMAGE_IMPORT_BY_NAME pimp = rva (PIMAGE_IMPORT_BY_NAME, hm, pn->u1.AddressOfData);
+
+      if (strcmp (fh.name, (char *) pimp->Name) == 0)
+	{
+	  fh.origfn = putmem (pi, fh.hookfn);
+	  if (!fh.origfn)
+	    return false;
+	  hook_chain *hc;
+	  for (hc = &cygheap->hooks; hc->next; hc = hc->next)
+	    continue;
+	  hc->next = (hook_chain *) cmalloc (HEAP_1_HOOK, sizeof (hook_chain));
+	  hc->next->loc = (void **) pi;
+	  hc->next->func = fh.hookfn;
+	  hc->next->next = NULL;
+	  break;
+      }
+  }
+
+  return true;
+}
+
+void
+get_export (function_hook& fh)
+{
+  extern HMODULE cygwin_hmodule;
+  PIMAGE_DOS_HEADER pdh = (PIMAGE_DOS_HEADER) cygwin_hmodule;
+  if (pdh->e_magic != IMAGE_DOS_SIGNATURE)
+    return;
+  PIMAGE_NT_HEADERS pnt = (PIMAGE_NT_HEADERS) ((char *) pdh + pdh->e_lfanew);
+  if (pnt->Signature != IMAGE_NT_SIGNATURE || pnt->FileHeader.SizeOfOptionalHeader == 0)
+    return;
+  PIMAGE_EXPORT_DIRECTORY pexp =
+    rvacyg (PIMAGE_EXPORT_DIRECTORY,
+	 pnt->OptionalHeader.DataDirectory[IMAGE_DIRECTORY_ENTRY_EXPORT].VirtualAddress);
+  if (!pexp)
+    return;
+
+  PDWORD pfuncs = rvacyg (PDWORD, pexp->AddressOfFunctions);
+  PDWORD pnames = rvacyg (PDWORD, pexp->AddressOfNames);
+  for (DWORD i = 0; i < pexp->NumberOfNames; i++)
+    if (strcmp (fh.name, rvacyg (char *, pnames[i])) == 0)
+      {
+	fh.origfn = rvacyg (void *, pfuncs[i]);
+	break;
+      }
+}
+
+static const char *
+makename (const char *name, char *&buf, int& i, int inc)
+{
+  i += inc;
+  static const char *testers[] = {"NOTUSED", "64", "32"};
+  if (i < 0 || i >= (int) (sizeof (testers) / sizeof (testers[0])))
+    return NULL;
+  if (i)
+    {
+      __small_sprintf (buf, "_%s%s", name, testers[i]);
+      name = buf;
+    }
+  return name;
+}
+
+// Top level routine to find the EXE's imports, and redirect them
+void *
+hook_cygwin (const char *name, const void *fn)
+{
+  HMODULE hm = GetModuleHandle (NULL);
+  PIMAGE_NT_HEADERS pExeNTHdr = PEHeaderFromHModule (hm);
+
+  if (!pExeNTHdr)
+    return false;
+
+  DWORD importRVA = pExeNTHdr->OptionalHeader.DataDirectory
+		      [IMAGE_DIRECTORY_ENTRY_IMPORT].VirtualAddress;
+  if (!importRVA)
+    return false;
+
+  // Convert imports RVA to a usable pointer
+  PIMAGE_IMPORT_DESCRIPTOR pdfirst = rva (PIMAGE_IMPORT_DESCRIPTOR, hm, importRVA);
+
+  function_hook fh;
+  fh.origfn = NULL;
+  fh.hookfn = fn;
+  char *buf = (char *) alloca (strlen (name) + strlen ("64") + sizeof ("_"));
+  int i = -1;
+  while (!fh.origfn && (fh.name = makename (name, buf, i, 1)))
+    {
+      // Iterate through each import descriptor, and redirect if appropriate
+      for (PIMAGE_IMPORT_DESCRIPTOR pd = pdfirst; pd->FirstThunk; pd++)
+	{
+	  PSTR modname = rva (PSTR, hm, pd->Name);
+	  if (strcasematch (modname, "cygwin1.dll"))
+	    RedirectIAT (fh, pd, hm);
+	}
+    }
+
+  while (!fh.origfn && (fh.name = makename (name, buf, i, -1)))
+    get_export (fh);
+
+  return fh.origfn;
+}
+
+void
+ld_preload ()
+{
+  char *p = getenv ("LD_PRELOAD");
+  if (!p)
+    return;
+  char *s = (char *) alloca (strlen (p) + 1);
+  strcpy (s, p);
+  char *here = NULL;
+  for (p = strtok_r (s, " \t\n", &here); p; p = strtok_r (NULL, " \t\n", &here))
+    {
+      path_conv lib (p);
+      if (!LoadLibrary (lib))
+	{
+	  __seterrno ();
+	  api_fatal ("error while loading shared libraries: %s: "
+		     "cannot open shared object file: %s", p,
+		     strerror (get_errno ()));
+	}
+    }
+}
+
+void
+fixup_hooks_after_fork ()
+{
+  for (hook_chain *hc = &cygheap->hooks; (hc = hc->next); )
+    putmem ((PIMAGE_THUNK_DATA) hc->loc, hc->func);
+}

winsup/cygwin/include/sys/cygwin.h

@@ -49,6 +49,7 @@ struct __cygwin_perfile
 
 /* External interface stuff */
 
+/* Always add at the bottom.  Do not add new values in the middle. */
 typedef enum
   {
     CW_LOCK_PINFO,
@@ -78,7 +79,8 @@ typedef enum
     CW_GET_SHMLBA,
     CW_GET_UID_FROM_SID,
     CW_GET_GID_FROM_SID,
-    CW_GET_BINMODE
+    CW_GET_BINMODE,
+    CW_HOOK
   } cygwin_getinfo_types;
 
 #define CW_NEXTPID	0x80000000	/* or with pid to get next one */

winsup/cygwin/init.cc

@@ -108,6 +108,8 @@ respawn_wow64_process ()
 
 extern void __stdcall dll_crt0_0 ();
 
+HMODULE NO_COPY cygwin_hmodule;
+
 extern "C" int WINAPI
 dll_entry (HANDLE h, DWORD reason, void *static_load)
 {
@@ -116,6 +118,7 @@ dll_entry (HANDLE h, DWORD reason, void *static_load)
   switch (reason)
     {
     case DLL_PROCESS_ATTACH:
+      cygwin_hmodule = (HMODULE) h;
       /* Is the stack at an unusual high address?  Check if we're running on
 	 a 64 bit machine.  If so, respawn. */
       if (&is_64bit_machine >= (PBOOL) 0x400000

winsup/cygwin/select.cc

@@ -1394,6 +1394,7 @@ start_thread_socket (select_record *me, select_stuff *stuff)
 	SetHandleInformation ((HANDLE) si->exitsock, HANDLE_FLAG_INHERIT, 0);
       /* else
 	   too bad? */
+      select_printf ("opened new socket %p", _my_tls.locals.exitsock);
     }
 
   select_printf ("exitsock %p", si->exitsock);