From ff152e3fc8c7d38e08d9f9d70eb6109c878e1372 Mon Sep 17 00:00:00 2001 From: Ulrich Drepper Date: Thu, 14 May 1998 19:14:48 +0000 Subject: Update. 1998-05-14 13:25 Ulrich Drepper * inet/netinet/in.h: Add defines for multicast. Reported by Jeremy Hall . * stdlib/stdlib.h: Add prototypes for __setenv and __unsetenv. * sysdeps/generic/putenv.c: Use __setenv and __unsetenv, not setenv and unsetenv. Optimize _LIBC case. * sysdeps/generic/setenv.c: Prevent unnecessary memory leaks. Define functions with leading __. * time/tzfile.c: Correct handling of global variables daylight, timezone, and tzname. * time/tzset.c: Likewise. * timezone/Makefile (tests): Add tst-timezone. * timezone/tst-timezone.c: New file. 1998-05-14 10:35 Ulrich Drepper * timezone/asia: Update from tzdata1998d. * timezone/australasia: Likewise. * timezone/europe: Likewise. --- sysdeps/generic/setenv.c | 153 +++++++++++++++++++++++++++++++++++------------ 1 file changed, 114 insertions(+), 39 deletions(-) (limited to 'sysdeps/generic/setenv.c') diff --git a/sysdeps/generic/setenv.c b/sysdeps/generic/setenv.c index d4c5c87b15..69bd992832 100644 --- a/sysdeps/generic/setenv.c +++ b/sysdeps/generic/setenv.c @@ -1,4 +1,4 @@ -/* Copyright (C) 1992, 1995, 1996, 1997 Free Software Foundation, Inc. +/* Copyright (C) 1992, 1995, 1996, 1997, 1998 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 @@ -22,7 +22,7 @@ #include #if !_LIBC -# if !defined(errno) && !defined(HAVE_ERRNO_DECL) +# if !defined errno && !defined HAVE_ERRNO_DECL extern int errno; # endif # define __set_errno(ev) ((errno) = (ev)) @@ -58,9 +58,34 @@ __libc_lock_define_initialized (static, envlock) /* In the GNU C library we must keep the namespace clean. */ #ifdef _LIBC +# define setenv __setenv +# define unsetenv __unsetenv # define clearenv __clearenv #endif +/* In the GNU C library implementation we try to be more clever and + allow arbitrary many changes of the environment given that the used + values are from a small set. Outside glibc this will eat up all + memory after a while. */ +#if defined _LIBC || (defined HAVE_SEARCH_H && defined HAVE_TSEARCH) +# define USE_TSEARCH 1 +# include + +/* This is a pointer to the root of the search tree with the known + values. */ +static void *known_values; + +# define KNOWN_VALUE(Str) tfind (Str, &known_values, (__compar_fn_t) strcmp) +# define STORE_VALUE(Str) tsearch (Str, &known_values, (__compar_fn_t) strcmp) + +#else +# undef USE_TSEARCH + +# define KNOWN_VALUE(Str) NULL +# define STORE_VALUE(Str) do { } while (0) + +#endif + /* If this variable is not a null pointer we allocated the current environment. */ @@ -91,45 +116,56 @@ setenv (name, value, replace) if (__environ == NULL || *ep == NULL) { char **new_environ; +#ifdef USE_TSEARCH + char *new_value; +#endif - if (__environ == last_environ && __environ != NULL) - /* We allocated this space; we can extend it. */ - new_environ = (char **) realloc (last_environ, - (size + 2) * sizeof (char *)); - else - new_environ = (char **) malloc ((size + 2) * sizeof (char *)); - + /* We allocated this space; we can extend it. */ + new_environ = (char **) realloc (last_environ, + (size + 2) * sizeof (char *)); if (new_environ == NULL) { UNLOCK; return -1; } - new_environ[size] = malloc (namelen + 1 + vallen); + /* See whether the value is already known. */ +#ifdef USE_TSEARCH + new_value = alloca (namelen + 1 + vallen); +# ifdef _LIBC + __mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1), + value, vallen); +# else + memcpy (new_value, name, namelen); + new_value[namelen] = '='; + memcpy (&new_value[namelen + 1], value, vallen); +# endif + + new_environ[size] = KNOWN_VALUE (new_value); if (new_environ[size] == NULL) +#endif { - free ((char *) new_environ); - __set_errno (ENOMEM); - UNLOCK; - return -1; + new_environ[size] = malloc (namelen + 1 + vallen); + if (new_environ[size] == NULL) + { + __set_errno (ENOMEM); + UNLOCK; + return -1; + } + +#ifdef USE_TSEARCH + memcpy (new_environ[size], new_value, namelen + 1 + vallen); +#else + memcpy (new_environ[size], name, namelen); + new_environ[size][namelen] = '='; + memcpy (&new_environ[size][namelen + 1], value, vallen); +#endif } if (__environ != last_environ) memcpy ((char *) new_environ, (char *) __environ, size * sizeof (char *)); -#ifdef _LIBC - { - char *tmp = __mempcpy (new_environ[size], name, namelen); - *tmp++ = '='; - __mempcpy (tmp, value, vallen); - } -#else - memcpy (new_environ[size], name, namelen); - new_environ[size][namelen] = '='; - memcpy (&new_environ[size][namelen + 1], value, vallen); -#endif - new_environ[size + 1] = NULL; last_environ = __environ = new_environ; @@ -139,22 +175,48 @@ setenv (name, value, replace) size_t len = strlen (*ep); if (len + 1 < namelen + 1 + vallen) { + char *new_value; + char *np; + /* The existing string is too short; malloc a new one. */ - char *new = malloc (namelen + 1 + vallen); - if (new == NULL) +#ifdef USE_TSEARCH + new_value = alloca (namelen + 1 + vallen); +# ifdef _LIBC + __mempcpy (__mempcpy (__mempcpy (new_value, name, namelen), "=", 1), + value, vallen); +# else + memcpy (new_value, name, namelen); + new_value[namelen] = '='; + memcpy (&new_value[namelen + 1], value, vallen); +# endif + + np = KNOWN_VALUE (new_value); + if (np == NULL) +#endif { - UNLOCK; - return -1; - } - *ep = new; -#ifdef _LIBC - *((char *) __mempcpy (*ep, name, namelen)) = '='; + np = malloc (namelen + 1 + vallen); + if (np == NULL) + { + UNLOCK; + return -1; + } + +#ifdef USE_TSEARCH + memcpy (np, new_value, namelen + 1 + vallen); #else - memcpy (*ep, name, namelen); - (*ep)[namelen] = '='; + memcpy (np, name, namelen); + np[namelen] = '='; + memcpy (&np[namelen + 1], value, vallen); #endif + } + + /* Keep the old value around. */ + STORE_VALUE (*ep); + *ep = np; } - memcpy (&(*ep)[namelen + 1], value, vallen); + else + /* Overwrite the value part of the old value. */ + memcpy (&(*ep)[namelen + 1], value, vallen); } UNLOCK; @@ -171,11 +233,15 @@ unsetenv (name) LOCK; - for (ep = __environ; *ep; ++ep) + for (ep = __environ; *ep != NULL; ++ep) if (!strncmp (*ep, name, len) && (*ep)[len] == '=') { /* Found it. Remove this pointer by moving later ones back. */ char **dp = ep; + + /* Store the value so that we can reuse it later. */ + STORE_VALUE (ep); + do dp[0] = dp[1]; while (*dp++); @@ -195,7 +261,12 @@ clearenv () if (__environ == last_environ && __environ != NULL) { - /* We allocated this environment so we can free it. */ + /* We allocated this environment so we can free it. Store all the + strings. */ + char **ep = __environ; + while (*ep != NULL) + STORE_VALUE (*ep++); + free (__environ); last_environ = NULL; } @@ -208,6 +279,10 @@ clearenv () return 0; } #ifdef _LIBC +# undef setenv +# undef unsetenv # undef clearenv +weak_alias (__setenv, setenv) +weak_alias (__unsetenv, unsetenv) weak_alias (__clearenv, clearenv) #endif -- cgit 1.4.1