diff src/SDL_getenv.c @ 0:74212992fb08

Initial revision
author Sam Lantinga <slouken@lokigames.com>
date Thu, 26 Apr 2001 16:45:43 +0000
parents
children e3d0d44f6f2e
line wrap: on
line diff
--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/src/SDL_getenv.c	Thu Apr 26 16:45:43 2001 +0000
@@ -0,0 +1,171 @@
+
+/* Not all environments have a working getenv()/putenv() */
+
+#ifdef TEST_MAIN
+#define NEED_SDL_GETENV
+#endif
+
+#include "SDL_getenv.h"
+
+#ifdef NEED_SDL_GETENV
+
+#include <stdlib.h>
+#include <string.h>
+
+static char **SDL_env = (char **)0;
+
+/* Put a variable of the form "name=value" into the environment */
+int SDL_putenv(const char *variable)
+{
+	const char *name, *value;
+	int added;
+	int len, i;
+	char **new_env;
+	char *new_variable;
+
+	/* A little error checking */
+	if ( ! variable ) {
+		return(-1);
+	}
+	name = variable;
+	for ( value=variable; *value && (*value != '='); ++value ) {
+		/* Keep looking for '=' */ ;
+	}
+	if ( *value ) {
+		++value;
+	} else {
+		return(-1);
+	}
+
+	/* Allocate memory for the variable */
+	new_variable = (char *)malloc(strlen(variable)+1);
+	if ( ! new_variable ) {
+		return(-1);
+	}
+	strcpy(new_variable, variable);
+
+	/* Actually put it into the environment */
+	added = 0;
+	i = 0;
+	if ( SDL_env ) {
+		/* Check to see if it's already there... */
+		len = (value - name);
+		for ( ; SDL_env[i]; ++i ) {
+			if ( strncmp(SDL_env[i], name, len) == 0 ) {
+				break;
+			}
+		}
+		/* If we found it, just replace the entry */
+		if ( SDL_env[i] ) {
+			free(SDL_env[i]);
+			SDL_env[i] = new_variable;
+			added = 1;
+		}
+	}
+
+	/* Didn't find it in the environment, expand and add */
+	if ( ! added ) {
+		new_env = realloc(SDL_env, (i+2)*sizeof(char *));
+		if ( new_env ) {
+			SDL_env = new_env;
+			SDL_env[i++] = new_variable;
+			SDL_env[i++] = (char *)0;
+			added = 1;
+		} else {
+			free(new_variable);
+		}
+	}
+	return (added ? 0 : -1);
+}
+
+/* Retrieve a variable named "name" from the environment */
+char *SDL_getenv(const char *name)
+{
+	int len, i;
+	char *value;
+
+	value = (char *)0;
+	if ( SDL_env ) {
+		len = strlen(name);
+		for ( i=0; SDL_env[i] && !value; ++i ) {
+			if ( (strncmp(SDL_env[i], name, len) == 0) &&
+			     (SDL_env[i][len] == '=') ) {
+				value = &SDL_env[i][len+1];
+			}
+		}
+	}
+	return value;
+}
+
+#endif /* NEED_GETENV */
+
+#ifdef TEST_MAIN
+#include <stdio.h>
+
+int main(int argc, char *argv[])
+{
+	char *value;
+
+	printf("Checking for non-existent variable... ");
+	fflush(stdout);
+	if ( ! getenv("EXISTS") ) {
+		printf("okay\n");
+	} else {
+		printf("failed\n");
+	}
+	printf("Setting FIRST=VALUE1 in the environment... ");
+	fflush(stdout);
+	if ( putenv("FIRST=VALUE1") == 0 ) {
+		printf("okay\n");
+	} else {
+		printf("failed\n");
+	}
+	printf("Getting FIRST from the environment... ");
+	fflush(stdout);
+	value = getenv("FIRST");
+	if ( value && (strcmp(value, "VALUE1") == 0) ) {
+		printf("okay\n");
+	} else {
+		printf("failed\n");
+	}
+	printf("Setting SECOND=VALUE2 in the environment... ");
+	fflush(stdout);
+	if ( putenv("SECOND=VALUE2") == 0 ) {
+		printf("okay\n");
+	} else {
+		printf("failed\n");
+	}
+	printf("Getting SECOND from the environment... ");
+	fflush(stdout);
+	value = getenv("SECOND");
+	if ( value && (strcmp(value, "VALUE2") == 0) ) {
+		printf("okay\n");
+	} else {
+		printf("failed\n");
+	}
+	printf("Setting FIRST=NOVALUE in the environment... ");
+	fflush(stdout);
+	if ( putenv("FIRST=NOVALUE") == 0 ) {
+		printf("okay\n");
+	} else {
+		printf("failed\n");
+	}
+	printf("Getting FIRST from the environment... ");
+	fflush(stdout);
+	value = getenv("FIRST");
+	if ( value && (strcmp(value, "NOVALUE") == 0) ) {
+		printf("okay\n");
+	} else {
+		printf("failed\n");
+	}
+	printf("Checking for non-existent variable... ");
+	fflush(stdout);
+	if ( ! getenv("EXISTS") ) {
+		printf("okay\n");
+	} else {
+		printf("failed\n");
+	}
+	return(0);
+}
+#endif /* TEST_MAIN */
+