Initial revision
This commit is contained in:
parent
3ead667539
commit
b6a3c755c7
117
gdb/putenv.c
Normal file
117
gdb/putenv.c
Normal file
@ -0,0 +1,117 @@
|
||||
/****************************************************************/
|
||||
/* */
|
||||
/* putenv(3) */
|
||||
/* */
|
||||
/* Change or add an environment entry */
|
||||
/* */
|
||||
/****************************************************************/
|
||||
/* origination 1987-Oct-7 T. Holm */
|
||||
/****************************************************************/
|
||||
|
||||
/*
|
||||
From pacbell!ames!ll-xn!mit-eddie!uw-beaver!ssc-vax!uvicctr!tholm Wed May 4 23:40:52 1988
|
||||
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
|
||||
Reply-To: tholm@uvicctr.UUCP (Terrence W. Holm)
|
||||
Organization: University of Victoria, Victoria B.C. Canada
|
||||
Lines: 296
|
||||
|
||||
|
||||
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();
|
||||
|
||||
|
||||
/****************************************************************/
|
||||
/* */
|
||||
/* 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 '='. */
|
||||
/* */
|
||||
/****************************************************************/
|
||||
|
||||
|
||||
putenv( entry )
|
||||
char *entry;
|
||||
|
||||
{
|
||||
unsigned length;
|
||||
unsigned size;
|
||||
char **p;
|
||||
char **new_environ;
|
||||
|
||||
/* Find the length of the "NAME=" */
|
||||
|
||||
if ( (length=(unsigned) index(entry,'=')) == NULL )
|
||||
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( NULL );
|
||||
}
|
||||
|
||||
|
||||
/* 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(NULL);
|
||||
}
|
Loading…
x
Reference in New Issue
Block a user