add simplet init system

1 files changed, 38 insertions, 0 deletions

diff --git a/lib/exec/exec.c b/lib/exec/exec.c
new file mode 100644
index 0000000..42fd2c1
--- /dev/null
+++ b/lib/exec/exec.c
@@ -0,0 +1,38 @@
+#include "exec.h"
+#include "../sys/execve.h"
+#include "../env/env.h"
+#include "../cstr/cstr.h"
+#include "../malloc/malloc.h"
+
+int exec(const char **argv)
+{
+	const char *path = getenv("PATH");
+	const char *end;
+	char *filename;
+
+	while (*path) {
+		end = path;
+
+		while (*end && *end != ':') ++end;
+
+		filename = malloc((end - path) + cstr_length(argv[0]) + 2);
+
+		for (int i = 0; i < end - path; ++i)
+			filename[i] = path[i];
+
+		filename[end - path] = '/';
+
+		for (int i = 0; i < cstr_length(argv[0]) + 1; ++i)
+			filename[(end - path) + i + 1] = argv[0][i];
+
+		execve(filename, argv, getenvp());
+		free(filename);
+
+		path = end;
+
+		if (*path == ':')
+			++path;
+	}
+
+	return execve(argv[0], argv, getenvp());
+}