initial check-in, version 0.5.0

src/process/execvp.c

@@ -0,0 +1,34 @@
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <errno.h>
+
+extern char **__environ;
+
+int execvp(const char *file, char *const argv[])
+{
+	const char *p, *z, *path = getenv("PATH");
+	int l;
+
+	if (strchr(file, '/'))
+		return execve(file, argv, __environ);
+
+	/* FIXME: integer overflows */
+	if (!path) path = "/usr/local/bin:/bin:/usr/bin";
+	l = strlen(file) + strlen(path) + 2;
+
+	for(p=path; p && *p; p=z) {
+		char b[l];
+		z = strchr(p, ':');
+		if (z) {
+			memcpy(b, p, z-p);
+			b[z++-p] = 0;
+		} else strcpy(b, p);
+		strcat(b, "/");
+		strcat(b, file);
+		if (!access(b, X_OK))
+			return execve(b, argv, __environ);
+	}
+	errno = ENOENT;
+	return -1;
+}