binutils-gdb/gdb/environ.c

185 lines
4.5 KiB
C
Raw Blame History

This file contains invisible Unicode characters

This file contains invisible Unicode characters that are indistinguishable to humans but may be processed differently by a computer. If you think that this is intentional, you can safely ignore this warning. Use the Escape button to reveal them.

/* environ.c -- library for manipulating environments for GNU.
Copyright (C) 1986-2015 Free Software Foundation, Inc.
This program is free software; you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation; either version 3 of the License, or
(at your option) any later version.
This program 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 General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see <http://www.gnu.org/licenses/>. */
#define min(a, b) ((a) < (b) ? (a) : (b))
#define max(a, b) ((a) > (b) ? (a) : (b))
#include "defs.h"
#include "environ.h"
/* Return a new environment object. */
struct gdb_environ *
make_environ (void)
{
struct gdb_environ *e;
e = (struct gdb_environ *) xmalloc (sizeof (struct gdb_environ));
e->allocated = 10;
e->vector = (char **) xmalloc ((e->allocated + 1) * sizeof (char *));
e->vector[0] = 0;
return e;
}
/* Free an environment and all the strings in it. */
void
free_environ (struct gdb_environ *e)
{
char **vector = e->vector;
while (*vector)
xfree (*vector++);
xfree (e->vector);
xfree (e);
}
/* Copy the environment given to this process into E.
Also copies all the strings in it, so we can be sure
that all strings in these environments are safe to free. */
void
init_environ (struct gdb_environ *e)
{
extern char **environ;
int i;
if (environ == NULL)
return;
for (i = 0; environ[i]; i++) /*EMPTY */ ;
if (e->allocated < i)
{
e->allocated = max (i, e->allocated + 10);
e->vector = (char **) xrealloc ((char *) e->vector,
(e->allocated + 1) * sizeof (char *));
}
memcpy (e->vector, environ, (i + 1) * sizeof (char *));
while (--i >= 0)
{
int len = strlen (e->vector[i]);
char *newobj = (char *) xmalloc (len + 1);
memcpy (newobj, e->vector[i], len + 1);
e->vector[i] = newobj;
}
}
/* Return the vector of environment E.
This is used to get something to pass to execve. */
char **
environ_vector (struct gdb_environ *e)
{
return e->vector;
}
/* Return the value in environment E of variable VAR. */
char *
get_in_environ (const struct gdb_environ *e, const char *var)
{
int len = strlen (var);
char **vector = e->vector;
char *s;
for (; (s = *vector) != NULL; vector++)
if (strncmp (s, var, len) == 0 && s[len] == '=')
return &s[len + 1];
return 0;
}
/* Store the value in E of VAR as VALUE. */
void
set_in_environ (struct gdb_environ *e, const char *var, const char *value)
{
int i;
int len = strlen (var);
char **vector = e->vector;
char *s;
for (i = 0; (s = vector[i]) != NULL; i++)
if (strncmp (s, var, len) == 0 && s[len] == '=')
break;
if (s == 0)
{
if (i == e->allocated)
{
e->allocated += 10;
vector = (char **) xrealloc ((char *) vector,
(e->allocated + 1) * sizeof (char *));
e->vector = vector;
}
vector[i + 1] = 0;
}
else
xfree (s);
s = (char *) xmalloc (len + strlen (value) + 2);
strcpy (s, var);
strcat (s, "=");
strcat (s, value);
vector[i] = s;
/* This used to handle setting the PATH and GNUTARGET variables
specially. The latter has been replaced by "set gnutarget"
(which has worked since GDB 4.11). The former affects searching
the PATH to find SHELL, and searching the PATH to find the
argument of "symbol-file" or "exec-file". Maybe we should have
some kind of "set exec-path" for that. But in any event, having
"set env" affect anything besides the inferior is a bad idea.
What if we want to change the environment we pass to the program
without afecting GDB's behavior? */
return;
}
/* Remove the setting for variable VAR from environment E. */
void
unset_in_environ (struct gdb_environ *e, const char *var)
{
int len = strlen (var);
char **vector = e->vector;
char *s;
for (; (s = *vector) != NULL; vector++)
{
if (strncmp (s, var, len) == 0 && s[len] == '=')
{
xfree (s);
/* Walk through the vector, shuffling args down by one, including
the NULL terminator. Can't use memcpy() here since the regions
overlap, and memmove() might not be available. */
while ((vector[0] = vector[1]) != NULL)
{
vector++;
}
break;
}
}
}