Commit 077d0a39 authored by Willy Tarreau's avatar Willy Tarreau Committed by Paul E. McKenney
Browse files

tools/nolibc/stdlib: add a simple getenv() implementation 



This implementation relies on an extern definition of the environ
variable, that the caller must declare and initialize from envp.

Signed-off-by: default avatarWilly Tarreau <w@1wt.eu>
Signed-off-by: default avatarPaul E. McKenney <paulmck@kernel.org>
parent 170b230d

tools/include/nolibc/stdlib.h

+23 −0
Original line number Diff line number Diff line
@@ -60,6 +60,29 @@ int atoi(const char *s) 
	return atol(s);

}



/* Tries to find the environment variable named <name> in the environment array

 * pointed to by global variable "environ" which must be declared as a char **,

 * and must be terminated by a NULL (it is recommended to set this variable to

 * the "envp" argument of main()). If the requested environment variable exists

 * its value is returned otherwise NULL is returned.

 */

static __attribute__((unused))

char *getenv(const char *name)

{

	extern char **environ;

	int idx, i;



	if (environ) {

		for (idx = 0; environ[idx]; idx++) {

			for (i = 0; name[i] && name[i] == environ[idx][i];)

				i++;

			if (!name[i] && environ[idx][i] == '=')

				return &environ[idx][i+1];

		}

	}

	return NULL;

}



/* Converts the unsigned long integer <in> to its hex representation into

 * buffer <buffer>, which must be long enough to store the number and the

 * trailing zero (17 bytes for "ffffffffffffffff" or 9 for "ffffffff"). The