mirror of
https://sourceware.org/git/binutils-gdb.git
synced 2024-11-27 03:51:15 +08:00
619fd1455b
warnings about comparisons of integer with pointer when NULL is defined as ((void *) 0) rather than just a bare 0.
110 lines
2.7 KiB
C
110 lines
2.7 KiB
C
/****************************************************************/
|
|
/* */
|
|
/* putenv(3) */
|
|
/* */
|
|
/* Change or add an environment entry */
|
|
/* */
|
|
/****************************************************************/
|
|
/* origination 1987-Oct-7 T. Holm */
|
|
/****************************************************************/
|
|
|
|
/*
|
|
Path: hoptoad!pacbell!ames!ll-xn!mit-eddie!uw-beaver!ssc-vax!uvicctr!tholm
|
|
From: tholm@uvicctr.UUCP (Terrence W. Holm)
|
|
Newsgroups: comp.os.minix
|
|
Subject: putenv(3)
|
|
Message-ID: <395@uvicctr.UUCP>
|
|
Date: 5 May 88 06:40:52 GMT
|
|
Organization: University of Victoria, Victoria B.C. Canada
|
|
|
|
EFTH Minix report #2 - May 1988 - putenv(3)
|
|
|
|
This is an implementation of putenv(3) that we
|
|
wrote for Minix. Please consider this a public
|
|
domain program.
|
|
*/
|
|
|
|
#include <stdio.h>
|
|
|
|
#define PSIZE sizeof(char *)
|
|
|
|
extern char **environ;
|
|
|
|
char *index();
|
|
char *malloc();
|
|
|
|
/****************************************************************/
|
|
/* */
|
|
/* int */
|
|
/* putenv( entry ) */
|
|
/* */
|
|
/* The "entry" should follow the form */
|
|
/* "NAME=VALUE". This routine will search the */
|
|
/* user environment for "NAME" and replace its */
|
|
/* value with "VALUE". */
|
|
/* */
|
|
/* Note that "entry" is not copied, it is used */
|
|
/* as the environment entry. This means that it */
|
|
/* must not be unallocated or otherwise modifed */
|
|
/* by the caller, unless it is replaced by a */
|
|
/* subsequent putenv(). */
|
|
/* */
|
|
/* If the name is not found in the environment, */
|
|
/* then a new vector of pointers is allocated, */
|
|
/* "entry" is put at the end and the global */
|
|
/* variable "environ" is updated. */
|
|
/* */
|
|
/* This function normally returns NULL, but -1 */
|
|
/* is returned if it can not allocate enough */
|
|
/* space using malloc(3), or "entry" does not */
|
|
/* contain a '='. */
|
|
/* */
|
|
/****************************************************************/
|
|
|
|
|
|
int
|
|
putenv( entry )
|
|
char *entry;
|
|
{
|
|
unsigned length;
|
|
unsigned size;
|
|
char **p;
|
|
char **new_environ;
|
|
|
|
/* Find the length of the "NAME=" */
|
|
|
|
if ( (length=(unsigned) index(entry,'=')) == 0 )
|
|
return( -1 );
|
|
|
|
length = length - (unsigned) entry + 1;
|
|
|
|
|
|
/* Scan through the environment looking for "NAME=" */
|
|
|
|
for ( p=environ; *p != 0 ; p++ )
|
|
if ( strncmp( entry, *p, length ) == 0 )
|
|
{
|
|
*p = entry;
|
|
return( 0 );
|
|
}
|
|
|
|
|
|
/* The name was not found, build a bigger environment */
|
|
|
|
size = p - environ;
|
|
|
|
new_environ = (char **) malloc( (size+2)*PSIZE );
|
|
|
|
if ( new_environ == NULL )
|
|
return( -1 );
|
|
|
|
bcopy( (char *) environ, (char *) new_environ, size*PSIZE );
|
|
|
|
new_environ[size] = entry;
|
|
new_environ[size+1] = NULL;
|
|
|
|
environ = new_environ;
|
|
|
|
return(0);
|
|
}
|