Rewrite getenv(3), setenv(3), unsetenv(3) and clearenv(3).
This commit is contained in:
parent
af9ea5df04
commit
e91cde379a
|
@ -127,6 +127,25 @@ If there is ever going to be a path limit, it'll probably be either this value
|
||||||
or higher. Ideally, your programs ought to work with paths of any reasonable
|
or higher. Ideally, your programs ought to work with paths of any reasonable
|
||||||
length.
|
length.
|
||||||
|
|
||||||
|
putenv
|
||||||
|
------
|
||||||
|
|
||||||
|
This is a poorly designed interface for manipulating the environment which
|
||||||
|
interacts quite badly with interfaces such as setenv and unsetenv. The major
|
||||||
|
problem is that putenv makes the input string itself part of the environment,
|
||||||
|
but setenv makes a copy of the input string part of the environment. This means
|
||||||
|
that unsetenv (as well as putenv and setenv when changing an existing variable)
|
||||||
|
has to somehow know whether the a given entry in environ was allocated by setenv
|
||||||
|
and whether to free it. This isn't helped by the fact that the environ symbol
|
||||||
|
is publicly accessible and callers of putenv can change the environment by
|
||||||
|
editing the string the caller inserted. This means that the implementations of
|
||||||
|
setenv and unsetenv must do a considerable amount of book-keeping behind the
|
||||||
|
scenes to figure out whether a string was allocated by setenv or face memory
|
||||||
|
leaks when environment variables are changed or unset. The solution to get rid
|
||||||
|
of all the needless complexity putenv forces upon the other functions is simply:
|
||||||
|
Don't provide putenv in the first place and fix any software that uses putenv to
|
||||||
|
just call setenv instead.
|
||||||
|
|
||||||
sdl-config
|
sdl-config
|
||||||
----------
|
----------
|
||||||
|
|
||||||
|
|
|
@ -371,15 +371,18 @@ stdio/vscanf.o \
|
||||||
stdlib/atexit.o \
|
stdlib/atexit.o \
|
||||||
stdlib/canonicalize_file_name_at.o \
|
stdlib/canonicalize_file_name_at.o \
|
||||||
stdlib/canonicalize_file_name.o \
|
stdlib/canonicalize_file_name.o \
|
||||||
stdlib/env.o \
|
stdlib/clearenv.o \
|
||||||
stdlib/_Exit.o \
|
stdlib/_Exit.o \
|
||||||
stdlib/exit.o \
|
stdlib/exit.o \
|
||||||
|
stdlib/getenv.o \
|
||||||
stdlib/mkstemp.o \
|
stdlib/mkstemp.o \
|
||||||
stdlib/mktemp.o \
|
stdlib/mktemp.o \
|
||||||
stdlib/on_exit.o \
|
stdlib/on_exit.o \
|
||||||
stdlib/rand.o \
|
stdlib/rand.o \
|
||||||
stdlib/realpath.o \
|
stdlib/realpath.o \
|
||||||
|
stdlib/setenv.o \
|
||||||
stdlib/system.o \
|
stdlib/system.o \
|
||||||
|
stdlib/unsetenv.o \
|
||||||
sys/display/dispmsg_issue.o \
|
sys/display/dispmsg_issue.o \
|
||||||
sys/ioctl/ioctl.o \
|
sys/ioctl/ioctl.o \
|
||||||
sys/kernelinfo/kernelinfo.o \
|
sys/kernelinfo/kernelinfo.o \
|
||||||
|
@ -470,6 +473,7 @@ unistd/confstr.o \
|
||||||
unistd/dup2.o \
|
unistd/dup2.o \
|
||||||
unistd/dup3.o \
|
unistd/dup3.o \
|
||||||
unistd/dup.o \
|
unistd/dup.o \
|
||||||
|
unistd/environ.o \
|
||||||
unistd/execle.o \
|
unistd/execle.o \
|
||||||
unistd/execl.o \
|
unistd/execl.o \
|
||||||
unistd/execlp.o \
|
unistd/execlp.o \
|
||||||
|
|
|
@ -88,10 +88,12 @@ void* bsearch(const void*, const void*, size_t, size_t, int (*)(const void*, con
|
||||||
void* calloc(size_t, size_t);
|
void* calloc(size_t, size_t);
|
||||||
char* canonicalize_file_name(const char* path);
|
char* canonicalize_file_name(const char* path);
|
||||||
char* canonicalize_file_name_at(int dirfd, const char* path);
|
char* canonicalize_file_name_at(int dirfd, const char* path);
|
||||||
|
int clearenv(void);
|
||||||
div_t div(int, int);
|
div_t div(int, int);
|
||||||
void exit(int) __attribute__ ((__noreturn__));
|
void exit(int) __attribute__ ((__noreturn__));
|
||||||
void _Exit(int status) __attribute__ ((__noreturn__));
|
void _Exit(int status) __attribute__ ((__noreturn__));
|
||||||
void free(void*);
|
void free(void*);
|
||||||
|
char* getenv(const char*);
|
||||||
long labs(long);
|
long labs(long);
|
||||||
ldiv_t ldiv(long, long);
|
ldiv_t ldiv(long, long);
|
||||||
long long llabs(long long);
|
long long llabs(long long);
|
||||||
|
@ -105,7 +107,6 @@ int mkstemp(char*);
|
||||||
char* mktemp(char* templ);
|
char* mktemp(char* templ);
|
||||||
#endif
|
#endif
|
||||||
int on_exit(void (*function)(int, void*), void* arg);
|
int on_exit(void (*function)(int, void*), void* arg);
|
||||||
int putenv(char*);
|
|
||||||
void qsort(void*, size_t, size_t, int (*)(const void*, const void*));
|
void qsort(void*, size_t, size_t, int (*)(const void*, const void*));
|
||||||
int rand(void);
|
int rand(void);
|
||||||
void* realloc(void*, size_t);
|
void* realloc(void*, size_t);
|
||||||
|
@ -124,23 +125,6 @@ int unsetenv(const char*);
|
||||||
size_t wcstombs(char* __restrict, const wchar_t *__restrict, size_t);
|
size_t wcstombs(char* __restrict, const wchar_t *__restrict, size_t);
|
||||||
int wctomb(char*, wchar_t);
|
int wctomb(char*, wchar_t);
|
||||||
|
|
||||||
#if defined(_SORTIX_SOURCE) || defined(_WANT_SORTIX_ENV)
|
|
||||||
const char* const* getenviron(void);
|
|
||||||
size_t envlength(void);
|
|
||||||
const char* getenvindexed(size_t index);
|
|
||||||
const char* sortix_getenv(const char* name);
|
|
||||||
#endif
|
|
||||||
#if (defined(_SOURCE_SOURCE) && __SORTIX_STDLIB_REDIRECTS) || \
|
|
||||||
defined(_WANT_SORTIX_ENV)
|
|
||||||
const char* getenv(const char* name) asm ("sortix_getenv");
|
|
||||||
#else
|
|
||||||
char* getenv(const char*);
|
|
||||||
#endif
|
|
||||||
#if defined(_SORTIX_SOURCE) || defined(_SVID_SOURCE) || defined(_XOPEN_SOURCE) \
|
|
||||||
|| defined(_GNU_SOURCE) || defined(_BSD_SOURCE)
|
|
||||||
int clearenv(void);
|
|
||||||
#endif
|
|
||||||
|
|
||||||
#if defined(__is_sortix_libc)
|
#if defined(__is_sortix_libc)
|
||||||
struct exit_handler
|
struct exit_handler
|
||||||
{
|
{
|
||||||
|
|
|
@ -295,8 +295,11 @@ typedef __pid_t pid_t;
|
||||||
typedef __useconds_t useconds_t;
|
typedef __useconds_t useconds_t;
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
#if defined(_WANT_ENVIRON)
|
|
||||||
extern char** environ;
|
extern char** environ;
|
||||||
|
#if defined(__is_sortix_libc)
|
||||||
|
extern char** __environ_malloced;
|
||||||
|
extern size_t __environ_used;
|
||||||
|
extern size_t __environ_length;
|
||||||
#endif
|
#endif
|
||||||
|
|
||||||
/* TODO: These are not implemented in sortix libc yet. */
|
/* TODO: These are not implemented in sortix libc yet. */
|
||||||
|
|
|
@ -0,0 +1,38 @@
|
||||||
|
/*******************************************************************************
|
||||||
|
|
||||||
|
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||||
|
|
||||||
|
This file is part of the Sortix C Library.
|
||||||
|
|
||||||
|
The Sortix C Library is free software: you can redistribute it and/or modify
|
||||||
|
it under the terms of the GNU Lesser General Public License as published by
|
||||||
|
the Free Software Foundation, either version 3 of the License, or (at your
|
||||||
|
option) any later version.
|
||||||
|
|
||||||
|
The Sortix C Library is distributed in the hope that it will be useful, but
|
||||||
|
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
||||||
|
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
|
||||||
|
License for more details.
|
||||||
|
|
||||||
|
You should have received a copy of the GNU Lesser General Public License
|
||||||
|
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
|
||||||
|
stdlib/clearenv.cpp
|
||||||
|
Clear the environment and set environ to NULL.
|
||||||
|
|
||||||
|
*******************************************************************************/
|
||||||
|
|
||||||
|
#include <stdlib.h>
|
||||||
|
#include <unistd.h>
|
||||||
|
|
||||||
|
extern "C" int clearenv()
|
||||||
|
{
|
||||||
|
if ( environ == __environ_malloced )
|
||||||
|
{
|
||||||
|
for ( size_t i = 0; environ[i]; i++ )
|
||||||
|
free(environ[i]);
|
||||||
|
free(environ);
|
||||||
|
}
|
||||||
|
environ = NULL;
|
||||||
|
return 0;
|
||||||
|
}
|
|
@ -1,200 +0,0 @@
|
||||||
/*******************************************************************************
|
|
||||||
|
|
||||||
Copyright(C) Jonas 'Sortie' Termansen 2012.
|
|
||||||
|
|
||||||
This file is part of the Sortix C Library.
|
|
||||||
|
|
||||||
The Sortix C Library is free software: you can redistribute it and/or modify
|
|
||||||
it under the terms of the GNU Lesser General Public License as published by
|
|
||||||
the Free Software Foundation, either version 3 of the License, or (at your
|
|
||||||
option) any later version.
|
|
||||||
|
|
||||||
The Sortix C Library is distributed in the hope that it will be useful, but
|
|
||||||
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
|
||||||
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
|
|
||||||
License for more details.
|
|
||||||
|
|
||||||
You should have received a copy of the GNU Lesser General Public License
|
|
||||||
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
|
|
||||||
|
|
||||||
stdlib/env.cpp
|
|
||||||
Environmental variables utilities.
|
|
||||||
|
|
||||||
*******************************************************************************/
|
|
||||||
|
|
||||||
#include <stddef.h>
|
|
||||||
#include <stdlib.h>
|
|
||||||
#include <string.h>
|
|
||||||
#include <stdio.h>
|
|
||||||
#include <errno.h>
|
|
||||||
|
|
||||||
/* Since legacy applications rely on being able to modify the environ variable,
|
|
||||||
we have to keep track of whether it is what we expect and whether we know the
|
|
||||||
size of it. If it changed, we need to recount, as well as malloc a copy of it
|
|
||||||
if we wish to make changes. */
|
|
||||||
extern "C" { char** environ = NULL; }
|
|
||||||
static char** environ_malloced = NULL;
|
|
||||||
static char** environ_counted = NULL;
|
|
||||||
size_t environlen = 0;
|
|
||||||
size_t environroom = 0;
|
|
||||||
|
|
||||||
static inline bool environismalloced()
|
|
||||||
{
|
|
||||||
return environ && environ == environ_malloced;
|
|
||||||
}
|
|
||||||
|
|
||||||
extern "C" const char* const* getenviron(void)
|
|
||||||
{
|
|
||||||
return environ;
|
|
||||||
}
|
|
||||||
|
|
||||||
extern "C" size_t envlength(void)
|
|
||||||
{
|
|
||||||
if ( !environ ) { return 0; }
|
|
||||||
if ( environ_counted != environ )
|
|
||||||
{
|
|
||||||
size_t count = 0;
|
|
||||||
while ( environ[count] ) { count++; }
|
|
||||||
environ_counted = environ;
|
|
||||||
environlen = count;
|
|
||||||
}
|
|
||||||
return environlen;
|
|
||||||
}
|
|
||||||
|
|
||||||
extern "C" const char* getenvindexed(size_t index)
|
|
||||||
{
|
|
||||||
if ( envlength() <= index ) { errno = EBOUND; return NULL; }
|
|
||||||
return environ[index];
|
|
||||||
}
|
|
||||||
|
|
||||||
extern "C" const char* sortix_getenv(const char* name)
|
|
||||||
{
|
|
||||||
size_t equalpos = strcspn(name, "=");
|
|
||||||
if ( name[equalpos] == '=' ) { return NULL; }
|
|
||||||
size_t namelen = equalpos;
|
|
||||||
size_t envlen = envlength();
|
|
||||||
for ( size_t i = 0; i < envlen; i++ )
|
|
||||||
{
|
|
||||||
if ( strncmp(name, environ[i], namelen) ) { continue; }
|
|
||||||
if ( environ[i][namelen] != '=' ) { continue; }
|
|
||||||
return environ[i] + namelen + 1;
|
|
||||||
}
|
|
||||||
return NULL;
|
|
||||||
}
|
|
||||||
|
|
||||||
extern "C" char* getenv(const char* name)
|
|
||||||
{
|
|
||||||
return (char*) sortix_getenv(name);
|
|
||||||
}
|
|
||||||
|
|
||||||
static bool makeenvironmalloced()
|
|
||||||
{
|
|
||||||
if ( environismalloced() ) { return true; }
|
|
||||||
size_t envlen = envlength();
|
|
||||||
size_t newenvlen = envlen;
|
|
||||||
size_t newenvsize = sizeof(char*) * (newenvlen+1);
|
|
||||||
char** newenviron = (char**) malloc(newenvsize);
|
|
||||||
if ( !newenviron ) { return false; }
|
|
||||||
size_t sofar = 0;
|
|
||||||
for ( size_t i = 0; i < envlen; i++ )
|
|
||||||
{
|
|
||||||
newenviron[i] = strdup(environ[i]);
|
|
||||||
if ( !newenviron[i] ) { goto cleanup; }
|
|
||||||
sofar = i;
|
|
||||||
}
|
|
||||||
newenviron[envlen] = NULL;
|
|
||||||
environlen = environroom = newenvlen;
|
|
||||||
environ = environ_malloced = environ_counted = newenviron;
|
|
||||||
return true;
|
|
||||||
cleanup:
|
|
||||||
for ( size_t i = 0; i < sofar; i++ ) { free(newenviron[i]); }
|
|
||||||
free(newenviron);
|
|
||||||
return false;
|
|
||||||
}
|
|
||||||
|
|
||||||
extern "C" int clearenv(void)
|
|
||||||
{
|
|
||||||
if ( !environ ) { return 0; }
|
|
||||||
if ( environismalloced() )
|
|
||||||
{
|
|
||||||
for ( char** varp = environ; *varp; varp++ ) { free(*varp); }
|
|
||||||
free(environ);
|
|
||||||
}
|
|
||||||
environ = environ_counted = environ_malloced = NULL;
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
static bool doputenv(char* str, char* freeme, bool overwrite)
|
|
||||||
{
|
|
||||||
if ( !makeenvironmalloced() ) { free(freeme); return false; }
|
|
||||||
size_t strvarnamelen = strcspn(str, "=");
|
|
||||||
for ( size_t i = 0; i < envlength(); i++ )
|
|
||||||
{
|
|
||||||
char* var = environ[i];
|
|
||||||
if ( strncmp(str, var, strvarnamelen) ) { continue; }
|
|
||||||
if ( !overwrite ) { free(freeme); return true; }
|
|
||||||
free(var);
|
|
||||||
environ[i] = str;
|
|
||||||
return true;
|
|
||||||
}
|
|
||||||
if ( environlen == environroom )
|
|
||||||
{
|
|
||||||
size_t newenvironroom = environroom ? 2 * environroom : 16;
|
|
||||||
size_t newenvironsize = sizeof(char*) * (newenvironroom+1);
|
|
||||||
char** newenviron = (char**) realloc(environ, newenvironsize);
|
|
||||||
if ( !newenviron ) { free(freeme); return false; }
|
|
||||||
environ = environ_malloced = environ_counted = newenviron;
|
|
||||||
environroom = newenvironroom;
|
|
||||||
}
|
|
||||||
environ[environlen++] = str;
|
|
||||||
environ[environlen] = NULL;
|
|
||||||
return true;
|
|
||||||
}
|
|
||||||
|
|
||||||
extern "C" int setenv(const char* name, const char* value, int overwrite)
|
|
||||||
{
|
|
||||||
if ( !name || !name[0] || strchr(name, '=') ) { errno = EINVAL; return -1; }
|
|
||||||
char* str = (char*) malloc(strlen(name) + 1 + strlen(value) + 1);
|
|
||||||
if ( !str ) { return -1; }
|
|
||||||
stpcpy(stpcpy(stpcpy(str, name), "="), value);
|
|
||||||
if ( !doputenv(str, str, overwrite) ) { return -1; }
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
extern "C" int putenv(char* str)
|
|
||||||
{
|
|
||||||
if ( !strchr(str, '=') ) { errno = EINVAL; return -1; }
|
|
||||||
// TODO: HACK: This voilates POSIX as it mandates that callers must be able
|
|
||||||
// to modify the environment by modifying the string. However, this is bad
|
|
||||||
// design! It also means we got a memory leak since we can't safely free
|
|
||||||
// strings from the environment when overriding them. Therefore we create
|
|
||||||
// a copy of the strings here and use the copy instead. This is a problem
|
|
||||||
// for some applications that will subtly break.
|
|
||||||
char* strcopy = strdup(str);
|
|
||||||
if ( !strcopy )
|
|
||||||
return -1;
|
|
||||||
if ( !doputenv(strcopy, strcopy, true) ) { return -1; }
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
|
|
||||||
extern "C" int unsetenv(const char* name)
|
|
||||||
{
|
|
||||||
size_t equalpos = strcspn(name, "=");
|
|
||||||
if ( name[equalpos] == '=' ) { return 0; }
|
|
||||||
size_t namelen = equalpos;
|
|
||||||
size_t envlen = envlength();
|
|
||||||
for ( size_t i = 0; i < envlen; i++ )
|
|
||||||
{
|
|
||||||
if ( strncmp(name, environ[i], namelen) ) { continue; }
|
|
||||||
if ( environ[i][namelen] != '=' ) { continue; }
|
|
||||||
if ( environismalloced() )
|
|
||||||
{
|
|
||||||
char* str = environ[i];
|
|
||||||
free(str);
|
|
||||||
}
|
|
||||||
if ( i < envlen-1 ) { environ[i] = environ[envlen-1]; }
|
|
||||||
environ[--environlen] = NULL;
|
|
||||||
return 0;
|
|
||||||
}
|
|
||||||
return 0;
|
|
||||||
}
|
|
|
@ -0,0 +1,57 @@
|
||||||
|
/*******************************************************************************
|
||||||
|
|
||||||
|
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||||
|
|
||||||
|
This file is part of the Sortix C Library.
|
||||||
|
|
||||||
|
The Sortix C Library is free software: you can redistribute it and/or modify
|
||||||
|
it under the terms of the GNU Lesser General Public License as published by
|
||||||
|
the Free Software Foundation, either version 3 of the License, or (at your
|
||||||
|
option) any later version.
|
||||||
|
|
||||||
|
The Sortix C Library is distributed in the hope that it will be useful, but
|
||||||
|
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
||||||
|
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
|
||||||
|
License for more details.
|
||||||
|
|
||||||
|
You should have received a copy of the GNU Lesser General Public License
|
||||||
|
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
|
||||||
|
stdlib/getenv.cpp
|
||||||
|
Get an environment variable.
|
||||||
|
|
||||||
|
*******************************************************************************/
|
||||||
|
|
||||||
|
#include <errno.h>
|
||||||
|
#include <stdlib.h>
|
||||||
|
#include <string.h>
|
||||||
|
#include <unistd.h>
|
||||||
|
|
||||||
|
static inline
|
||||||
|
bool matches_environment_variable(const char* what,
|
||||||
|
const char* name, size_t name_length)
|
||||||
|
{
|
||||||
|
return !strncmp(what, name, name_length) && what[name_length] == '=';
|
||||||
|
}
|
||||||
|
|
||||||
|
extern "C" char* getenv(const char* name)
|
||||||
|
{
|
||||||
|
if ( !name )
|
||||||
|
return errno = EINVAL, (char*) NULL;
|
||||||
|
|
||||||
|
// Verify the name doesn't contain a '=' character.
|
||||||
|
size_t name_length = 0;
|
||||||
|
while ( name[name_length] )
|
||||||
|
if ( name[name_length++] == '=' )
|
||||||
|
return errno = EINVAL, (char*) NULL;
|
||||||
|
|
||||||
|
if ( !environ )
|
||||||
|
return NULL;
|
||||||
|
|
||||||
|
// Find the environment variable with the given name.
|
||||||
|
for ( size_t i = 0; environ[i]; i++ )
|
||||||
|
if ( matches_environment_variable(environ[i], name, name_length) )
|
||||||
|
return environ[i] + name_length + 1;
|
||||||
|
|
||||||
|
return NULL;
|
||||||
|
}
|
|
@ -0,0 +1,176 @@
|
||||||
|
/*******************************************************************************
|
||||||
|
|
||||||
|
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||||
|
|
||||||
|
This file is part of the Sortix C Library.
|
||||||
|
|
||||||
|
The Sortix C Library is free software: you can redistribute it and/or modify
|
||||||
|
it under the terms of the GNU Lesser General Public License as published by
|
||||||
|
the Free Software Foundation, either version 3 of the License, or (at your
|
||||||
|
option) any later version.
|
||||||
|
|
||||||
|
The Sortix C Library is distributed in the hope that it will be useful, but
|
||||||
|
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
||||||
|
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
|
||||||
|
License for more details.
|
||||||
|
|
||||||
|
You should have received a copy of the GNU Lesser General Public License
|
||||||
|
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
|
||||||
|
stdlib/setenv.cpp
|
||||||
|
Set an environment variable.
|
||||||
|
|
||||||
|
*******************************************************************************/
|
||||||
|
|
||||||
|
#include <errno.h>
|
||||||
|
#include <stdlib.h>
|
||||||
|
#include <string.h>
|
||||||
|
#include <unistd.h>
|
||||||
|
|
||||||
|
static inline
|
||||||
|
bool matches_environment_variable(const char* what,
|
||||||
|
const char* name, size_t name_length)
|
||||||
|
{
|
||||||
|
return !strncmp(what, name, name_length) && what[name_length] == '=';
|
||||||
|
}
|
||||||
|
|
||||||
|
static char* create_entry(const char* name, size_t name_length,
|
||||||
|
const char* value, size_t value_length)
|
||||||
|
{
|
||||||
|
size_t result_length = name_length + 1 + value_length;
|
||||||
|
size_t result_size = sizeof(char) * (result_length + 1);
|
||||||
|
char* result = (char*) malloc(result_size);
|
||||||
|
if ( !result )
|
||||||
|
return NULL;
|
||||||
|
stpcpy(stpcpy(stpcpy(result, name), "="), value);
|
||||||
|
return result;
|
||||||
|
}
|
||||||
|
|
||||||
|
static bool set_entry_at(char** environ, size_t position,
|
||||||
|
const char* name, size_t name_length,
|
||||||
|
const char* value, size_t value_length)
|
||||||
|
{
|
||||||
|
char* new_entry = create_entry(name, name_length, value, value_length);
|
||||||
|
if ( !new_entry)
|
||||||
|
return false;
|
||||||
|
free(environ[position]);
|
||||||
|
environ[position] = new_entry;
|
||||||
|
return true;
|
||||||
|
}
|
||||||
|
|
||||||
|
static bool recover_environment()
|
||||||
|
{
|
||||||
|
// It is undefined behavior to change environ to another value (manually
|
||||||
|
// taking control of the environment) and reusing any of the pointers from
|
||||||
|
// the former environ array. A program that assigns to environ must use its
|
||||||
|
// own memory for the environ array and all the strings pointed to by it.
|
||||||
|
// TODO: Is that actually undefined behavior?
|
||||||
|
|
||||||
|
// Destroy the old environ array and its entries that we'll assume is no
|
||||||
|
// longer used as that would be undefined behavior as said above.
|
||||||
|
if ( __environ_malloced )
|
||||||
|
{
|
||||||
|
for ( size_t i = 0; i < __environ_used; i++ )
|
||||||
|
free(__environ_malloced[i]);
|
||||||
|
free(__environ_malloced);
|
||||||
|
__environ_malloced = 0;
|
||||||
|
__environ_length = 0;
|
||||||
|
__environ_used = 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
// Prepare a new environ array into which we'll store all the strings.
|
||||||
|
size_t environ_length = 0;
|
||||||
|
if ( environ )
|
||||||
|
while ( environ[environ_length] )
|
||||||
|
environ_length++;
|
||||||
|
size_t environ_size = sizeof(char*) * (environ_length + 1);
|
||||||
|
char** environ_malloced = (char**) malloc(environ_size);
|
||||||
|
if ( !environ_malloced )
|
||||||
|
return false;
|
||||||
|
|
||||||
|
// Duplicate all the environment variables into the new environment.
|
||||||
|
for ( size_t i = 0; i < environ_length; i++ )
|
||||||
|
{
|
||||||
|
if ( !(environ_malloced[i] = strdup(environ[i])) )
|
||||||
|
{
|
||||||
|
for ( size_t n = 0; n < i; n++ )
|
||||||
|
free(environ_malloced[n]);
|
||||||
|
free(environ_malloced);
|
||||||
|
return false;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
environ_malloced[environ_length] = NULL;
|
||||||
|
|
||||||
|
// Switch to the newly recovered environment.
|
||||||
|
environ = __environ_malloced = environ_malloced;
|
||||||
|
__environ_used = environ_length;
|
||||||
|
__environ_length = environ_length;
|
||||||
|
|
||||||
|
return true;
|
||||||
|
}
|
||||||
|
|
||||||
|
extern "C" int setenv(const char* name, const char* value, int overwrite)
|
||||||
|
{
|
||||||
|
if ( !name || !value )
|
||||||
|
return errno = EINVAL, -1;
|
||||||
|
|
||||||
|
// Verify the name doesn't contain a '=' character.
|
||||||
|
size_t name_length = 0;
|
||||||
|
while ( name[name_length] )
|
||||||
|
if ( name[name_length++] == '=' )
|
||||||
|
return errno = EINVAL, -1;
|
||||||
|
|
||||||
|
// Take back control of the environment if the user changed the environ
|
||||||
|
// pointer to something the user controls or if the environment has not been
|
||||||
|
// initialized yet besides the read-only initial environment.
|
||||||
|
if ( (!environ || environ != __environ_malloced) && !recover_environment() )
|
||||||
|
return -1;
|
||||||
|
|
||||||
|
size_t value_length = strlen(value);
|
||||||
|
|
||||||
|
// Attempt to locate an existing environment variable with this name.
|
||||||
|
for ( size_t i = 0; i < __environ_used; i++ )
|
||||||
|
{
|
||||||
|
char* previous_entry = environ[i];
|
||||||
|
if ( !matches_environment_variable(previous_entry, name, name_length) )
|
||||||
|
continue;
|
||||||
|
|
||||||
|
// Report success if the caller doesn't want us to change an existing
|
||||||
|
// environment variable, but still set the variable if not set yet.
|
||||||
|
if ( !overwrite )
|
||||||
|
return 0;
|
||||||
|
|
||||||
|
// Avoid the need to allocate a new string if there is room in the old
|
||||||
|
// allocation for the contents of the new string.
|
||||||
|
char* previous_value = previous_entry + name_length + 1;
|
||||||
|
size_t previous_value_length = strlen(previous_value);
|
||||||
|
if ( value_length <= previous_value_length )
|
||||||
|
{
|
||||||
|
strcpy(previous_value, value);
|
||||||
|
return 0;
|
||||||
|
}
|
||||||
|
|
||||||
|
// Insert the new entry in the environ array at the same location.
|
||||||
|
bool result = set_entry_at(environ, i, name, name_length, value, value_length);
|
||||||
|
return result ? 0 : -1;
|
||||||
|
}
|
||||||
|
|
||||||
|
// Expand the environ array if it is currently fully used such that we have
|
||||||
|
// room to insert the new entry below.
|
||||||
|
if ( __environ_used == __environ_length )
|
||||||
|
{
|
||||||
|
size_t new_length = __environ_length ? 2 * __environ_length : 16;
|
||||||
|
size_t new_size = sizeof(char*) * (new_length + 1);
|
||||||
|
char** new_environ = (char**) realloc(environ, new_size);
|
||||||
|
if ( !new_environ )
|
||||||
|
return -1;
|
||||||
|
environ = __environ_malloced = new_environ;
|
||||||
|
for ( size_t i = __environ_used; i <= new_length; i++ )
|
||||||
|
environ[i] = NULL;
|
||||||
|
__environ_length = new_length;
|
||||||
|
}
|
||||||
|
|
||||||
|
// Append the new entry to the environ array.
|
||||||
|
bool result = set_entry_at(environ, __environ_used++, name, name_length, value, value_length);
|
||||||
|
return result ? 0 : -1;
|
||||||
|
}
|
|
@ -0,0 +1,79 @@
|
||||||
|
/*******************************************************************************
|
||||||
|
|
||||||
|
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||||
|
|
||||||
|
This file is part of the Sortix C Library.
|
||||||
|
|
||||||
|
The Sortix C Library is free software: you can redistribute it and/or modify
|
||||||
|
it under the terms of the GNU Lesser General Public License as published by
|
||||||
|
the Free Software Foundation, either version 3 of the License, or (at your
|
||||||
|
option) any later version.
|
||||||
|
|
||||||
|
The Sortix C Library is distributed in the hope that it will be useful, but
|
||||||
|
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
||||||
|
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
|
||||||
|
License for more details.
|
||||||
|
|
||||||
|
You should have received a copy of the GNU Lesser General Public License
|
||||||
|
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
|
||||||
|
stdlib/unsetenv.cpp
|
||||||
|
Unset an environment variable.
|
||||||
|
|
||||||
|
*******************************************************************************/
|
||||||
|
|
||||||
|
#include <errno.h>
|
||||||
|
#include <stdlib.h>
|
||||||
|
#include <string.h>
|
||||||
|
#include <unistd.h>
|
||||||
|
|
||||||
|
static inline
|
||||||
|
bool matches_environment_variable(const char* what,
|
||||||
|
const char* name, size_t name_length)
|
||||||
|
{
|
||||||
|
return !strncmp(what, name, name_length) && what[name_length] == '=';
|
||||||
|
}
|
||||||
|
|
||||||
|
extern "C" int unsetenv(const char* name)
|
||||||
|
{
|
||||||
|
if ( !name )
|
||||||
|
return errno = EINVAL, -1;
|
||||||
|
|
||||||
|
// Verify the name doesn't contain a '=' character.
|
||||||
|
size_t name_length = 0;
|
||||||
|
while ( name[name_length] )
|
||||||
|
if ( name[name_length++] == '=' )
|
||||||
|
return errno = EINVAL, -1;
|
||||||
|
|
||||||
|
if ( !environ )
|
||||||
|
return 0;
|
||||||
|
|
||||||
|
// Delete all variables from the environment with the given name.
|
||||||
|
for ( size_t i = 0; environ[i]; i++ )
|
||||||
|
{
|
||||||
|
if ( matches_environment_variable(environ[i], name, name_length) )
|
||||||
|
{
|
||||||
|
// Free the string and move the array around in constant time if
|
||||||
|
// the setenv implementation is in control of the array.
|
||||||
|
if ( environ == __environ_malloced )
|
||||||
|
{
|
||||||
|
free(environ[i]);
|
||||||
|
environ[i] = environ[__environ_used-1];
|
||||||
|
environ[--__environ_used] = NULL;
|
||||||
|
}
|
||||||
|
|
||||||
|
// Otherwise, we'll simply clear that entry in environ, but we can't
|
||||||
|
// do it in constant time as we don't know how large the array is.
|
||||||
|
else
|
||||||
|
{
|
||||||
|
for ( size_t n = i; environ[n]; n++ )
|
||||||
|
environ[n] = environ[n+1];
|
||||||
|
}
|
||||||
|
|
||||||
|
// This entry was deleted so we'll need to process it again.
|
||||||
|
i--;
|
||||||
|
}
|
||||||
|
}
|
||||||
|
|
||||||
|
return 0;
|
||||||
|
}
|
|
@ -0,0 +1,30 @@
|
||||||
|
/*******************************************************************************
|
||||||
|
|
||||||
|
Copyright(C) Jonas 'Sortie' Termansen 2014.
|
||||||
|
|
||||||
|
This file is part of the Sortix C Library.
|
||||||
|
|
||||||
|
The Sortix C Library is free software: you can redistribute it and/or modify
|
||||||
|
it under the terms of the GNU Lesser General Public License as published by
|
||||||
|
the Free Software Foundation, either version 3 of the License, or (at your
|
||||||
|
option) any later version.
|
||||||
|
|
||||||
|
The Sortix C Library is distributed in the hope that it will be useful, but
|
||||||
|
WITHOUT ANY WARRANTY; without even the implied warranty of MERCHANTABILITY
|
||||||
|
or FITNESS FOR A PARTICULAR PURPOSE. See the GNU Lesser General Public
|
||||||
|
License for more details.
|
||||||
|
|
||||||
|
You should have received a copy of the GNU Lesser General Public License
|
||||||
|
along with the Sortix C Library. If not, see <http://www.gnu.org/licenses/>.
|
||||||
|
|
||||||
|
unistd/environ.cpp
|
||||||
|
Environment variables.
|
||||||
|
|
||||||
|
*******************************************************************************/
|
||||||
|
|
||||||
|
#include <unistd.h>
|
||||||
|
|
||||||
|
extern "C" { char** environ = NULL; }
|
||||||
|
extern "C" { char** __environ_malloced = NULL; }
|
||||||
|
extern "C" { size_t __environ_used = 0; }
|
||||||
|
extern "C" { size_t __environ_length = 0; }
|
14
utils/sh.cpp
14
utils/sh.cpp
|
@ -341,10 +341,8 @@ readcmd:
|
||||||
|
|
||||||
if ( !strcmp(argv[0], "env") )
|
if ( !strcmp(argv[0], "env") )
|
||||||
{
|
{
|
||||||
for ( size_t i = 0; i < envlength(); i++ )
|
for ( size_t i = 0; environ[i]; i++ )
|
||||||
{
|
printf("%s\n", environ[i]);
|
||||||
printf("%s\n", getenvindexed(i));
|
|
||||||
}
|
|
||||||
exit(0);
|
exit(0);
|
||||||
}
|
}
|
||||||
|
|
||||||
|
@ -481,8 +479,12 @@ int get_and_run_command(FILE* fp, const char* fpname, bool interactive,
|
||||||
|
|
||||||
if ( strchr(command, '=') && !strchr(command, ' ') && !strchr(command, '\t') )
|
if ( strchr(command, '=') && !strchr(command, ' ') && !strchr(command, '\t') )
|
||||||
{
|
{
|
||||||
if ( putenv(strdup(command)) )
|
const char* key = command;
|
||||||
error(1, errno, "putenv");
|
char* equal = strchr(command, '=');
|
||||||
|
*equal = '\0';
|
||||||
|
const char* value = equal + 1;
|
||||||
|
if ( setenv(key, value, 1) < 0 )
|
||||||
|
error(1, errno, "setenv");
|
||||||
return status = 0;
|
return status = 0;
|
||||||
}
|
}
|
||||||
|
|
||||||
|
|
Loading…
Reference in New Issue