1 files changed, 59 insertions, 0 deletions
diff --git a/lib/shell.c b/lib/shell.c
new file mode 100644
index 0000000..9a38b40
--- /dev/null
+++ b/lib/shell.c
@@ -0,0 +1,59 @@
+#include "lslib.h"
+
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+void setup_environment(const char *shell, bool new_env, bool clear_env, const struct passwd *pw) {
+	if (!shell || !shell[0])
+		shell = DEFAULT_SHELL;
+    
+    if (clear_env) {
+        const char* term;
+		term = getenv("TERM");
+		clearenv();
+		if (term)
+			xsetenv("TERM", term);
+		xsetenv("PATH", DEFAULT_PATH);
+    }
+
+    if (new_env) {
+	    xsetenv("USER",    pw->pw_name);
+	    xsetenv("LOGNAME", pw->pw_name);
+	    xsetenv("HOME",    pw->pw_dir);
+	    xsetenv("SHELL",   shell);
+    }
+}
+
+void exec_shell(const char *shell, bool loginshell, const char **additional_args) {
+
+    const char** args;
+
+	args = additional_args;
+	while (args && *args)
+		args++;
+
+	args = xzalloc(sizeof(args[0]) * (2 + (args - additional_args)));
+	
+    if (!shell || !shell[0])
+		shell = DEFAULT_SHELL;
+
+    args[0] = get_last_component(shell);    
+    
+    if (loginshell) {
+        size_t len = strlen(shell) + 2;
+        char* arg = xalloc(len);
+        arg[0] = '-';
+        memcpy(&arg[1], shell, len - 1);
+        args[0] = arg;
+    }
+
+    if (additional_args) {
+        int count = 0;
+        while (*additional_args)
+            args[++count] = *additional_args++;
+    }
+
+    execv(shell, (char**) args);
+    error("cannot execute '%s'", shell);
+}