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authorUlrich Drepper <drepper@redhat.com>2001-12-14 22:17:03 +0000
committerUlrich Drepper <drepper@redhat.com>2001-12-14 22:17:03 +0000
commit638621aff981fc5e9e5824d04c67ef2a7dfa4744 (patch)
treef81d717e5260b86d984b4767bcdecd48be253f30
parent0ce9cf883db2ec6bf8854828b4b57d03e050c5f2 (diff)
downloadglibc-638621aff981fc5e9e5824d04c67ef2a7dfa4744.tar.gz
glibc-638621aff981fc5e9e5824d04c67ef2a7dfa4744.tar.xz
glibc-638621aff981fc5e9e5824d04c67ef2a7dfa4744.zip
Update.
	* sysdeps/generic/strstr.c (strstr): Update.  New optimized version.
-rw-r--r--ChangeLog2
-rw-r--r--linuxthreads/ChangeLog6
-rw-r--r--linuxthreads/linuxthreads.texi11
-rw-r--r--linuxthreads/man/pthread_atfork.man13
-rw-r--r--sysdeps/generic/strstr.c121
5 files changed, 74 insertions, 79 deletions
diff --git a/ChangeLog b/ChangeLog
index 494741f98d..e4a4d65407 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,5 +1,7 @@
 2001-12-14  Ulrich Drepper  <drepper@redhat.com>
 
+	* sysdeps/generic/strstr.c (strstr): Update.  New optimized version.
+
 	* crypt/md5.h: Define md5_uintptr.
 
 2001-12-13  Ulrich Drepper  <drepper@redhat.com>
diff --git a/linuxthreads/ChangeLog b/linuxthreads/ChangeLog
index a926600e85..2b55b8fcfb 100644
--- a/linuxthreads/ChangeLog
+++ b/linuxthreads/ChangeLog
@@ -1,3 +1,9 @@
+2001-12-14  Ulrich Drepper  <drepper@redhat.com>
+
+	* man/pthread_atfork.man: Adjust description of mutex handling
+	after fork for current implementation.
+	* linuxthreads.texi: Likewise [PR libc/2519].
+
 2001-12-13  Andreas Schwab  <schwab@suse.de>
 
 	* specific.c (pthread_key_delete): Don't contact the thread
diff --git a/linuxthreads/linuxthreads.texi b/linuxthreads/linuxthreads.texi
index 9513a67a6a..b4d83c9dee 100644
--- a/linuxthreads/linuxthreads.texi
+++ b/linuxthreads/linuxthreads.texi
@@ -1395,12 +1395,10 @@ pocess image.
 To understand the purpose of @code{pthread_atfork}, recall that
 @code{fork} duplicates the whole memory space, including mutexes in
 their current locking state, but only the calling thread: other threads
-are not running in the child process. Thus, if a mutex is locked by a
-thread other than the thread calling @code{fork}, that mutex will remain
-locked forever in the child process, possibly blocking the execution of
-the child process. Or if some shared data, such as a linked list, was in the
-middle of being updated by a thread in the parent process, the child
-will get a copy of the incompletely updated data which it cannot use.
+are not running in the child process.  The mutexes are not usable after
+the @code{fork} and must be initialized with @code{pthread_mutex_init}
+in the child process.  This is a limitation of the current
+implementation and might or might not be present in future versions.
 
 To avoid this, install handlers with @code{pthread_atfork} as follows: have the
 @var{prepare} handler lock the mutexes (in locking order), and the
@@ -1627,4 +1625,3 @@ of a mapping of user threads to kernel threads.  It exists for source
 compatibility.  However, it will return the value that was set by the
 last call to @code{pthread_setconcurrency}.
 @end deftypefun
-
diff --git a/linuxthreads/man/pthread_atfork.man b/linuxthreads/man/pthread_atfork.man
index 4d06a56f8b..b682bed3ac 100644
--- a/linuxthreads/man/pthread_atfork.man
+++ b/linuxthreads/man/pthread_atfork.man
@@ -30,15 +30,10 @@ while the |parent| and |child| handlers are called in FIFO order
 To understand the purpose of !pthread_atfork!, recall that !fork!(2)
 duplicates the whole memory space, including mutexes in their current
 locking state, but only the calling thread: other threads are not
-running in the child process. Thus, if a mutex is locked by a thread
-other than the thread calling !fork!, that mutex will remain locked
-forever in the child process, possibly blocking the execution of the
-child process. To avoid this, install handlers with !pthread_atfork!
-as follows: the |prepare| handler locks the global mutexes (in locking
-order), and the |parent| and |child| handlers unlock them (in
-reverse order). Alternatively, |prepare| and |parent| can be set to
-!NULL! and |child| to a function that calls !pthread_mutex_init! on
-the global mutexes.
+running in the child process.  The mutexes are not usable after the
+!fork! and must be initialized with |pthread_mutex_init| in the child
+process.  This is a limitation of the current implementation and might
+or might not be present in future versions.
 
 .SH "RETURN VALUE"
 
diff --git a/sysdeps/generic/strstr.c b/sysdeps/generic/strstr.c
index 1409fbdeb6..ff295e0635 100644
--- a/sysdeps/generic/strstr.c
+++ b/sysdeps/generic/strstr.c
@@ -1,5 +1,5 @@
 /* Return the offset of one string within another.
-   Copyright (C) 1994, 1996, 1997, 2000 Free Software Foundation, Inc.
+   Copyright (C) 1994, 1996, 1997, 2000, 2001 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
    The GNU C Library is free software; you can redistribute it and/or
@@ -43,85 +43,80 @@ strstr (phaystack, pneedle)
      const char *phaystack;
      const char *pneedle;
 {
-  register const unsigned char *haystack, *needle;
-  register chartype b, c;
+  const unsigned char *haystack, *needle;
+  chartype b;
+  const unsigned char *rneedle;
 
   haystack = (const unsigned char *) phaystack;
-  needle = (const unsigned char *) pneedle;
 
-  b = *needle;
-  if (b != '\0')
+  if (b = *(needle = (const unsigned char *) pneedle))
     {
-      haystack--;				/* possible ANSI violation */
-      do
-	{
-	  c = *++haystack;
-	  if (c == '\0')
+      chartype c;
+      haystack--;		/* possible ANSI violation */
+
+      {
+	chartype a;
+	do
+	  if (!(a = *++haystack))
 	    goto ret0;
-	}
-      while (c != b);
+	while (a != b);
+      }
 
-      c = *++needle;
-      if (c == '\0')
+      if (!(c = *++needle))
 	goto foundneedle;
       ++needle;
       goto jin;
 
       for (;;)
-        {
-          register chartype a;
-	  register const unsigned char *rhaystack, *rneedle;
-
-	  do
-	    {
-	      a = *++haystack;
-	      if (a == '\0')
-		goto ret0;
-	      if (a == b)
-		break;
+	{
+	  {
+	    chartype a;
+	    if (0)
+	    jin:{
+		if ((a = *++haystack) == c)
+		  goto crest;
+	      }
+	    else
 	      a = *++haystack;
-	      if (a == '\0')
-		goto ret0;
-shloop:
-	      ;
-	    }
-          while (a != b);
-
-jin:	  a = *++haystack;
-	  if (a == '\0')
-	    goto ret0;
-
-	  if (a != c)
-	    goto shloop;
-
-	  rhaystack = haystack-- + 1;
-	  rneedle = needle;
-	  a = *rneedle;
-
-	  if (*rhaystack == a)
 	    do
 	      {
-		if (a == '\0')
-		  goto foundneedle;
-		++rhaystack;
-		a = *++needle;
-		if (*rhaystack != a)
-		  break;
-		if (a == '\0')
-		  goto foundneedle;
-		++rhaystack;
-		a = *++needle;
+		for (; a != b; a = *++haystack)
+		  {
+		    if (!a)
+		      goto ret0;
+		    if ((a = *++haystack) == b)
+		      break;
+		    if (!a)
+		      goto ret0;
+		  }
 	      }
-	    while (*rhaystack == a);
-
-	  needle = rneedle;		/* took the register-poor approach */
-
-	  if (a == '\0')
-	    break;
-        }
+	    while ((a = *++haystack) != c);
+	  }
+	crest:
+	  {
+	    chartype a;
+	    {
+	      const unsigned char *rhaystack;
+	      if (*(rhaystack = haystack-- + 1) == (a = *(rneedle = needle)))
+		do
+		  {
+		    if (!a)
+		      goto foundneedle;
+		    if (*++rhaystack != (a = *++needle))
+		      break;
+		    if (!a)
+		      goto foundneedle;
+		  }
+		while (*++rhaystack == (a = *++needle));
+	      needle = rneedle;	/* took the register-poor aproach */
+	    }
+	    if (!a)
+	      break;
+	  }
+	}
     }
 foundneedle:
-  return (char*) haystack;
+  return (char *) haystack;
 ret0:
   return 0;
 }