user/libc: execv()

4 files changed, 25 insertions, 7 deletions

diff --git a/src/shared/include/camellia/errno.h b/src/shared/include/camellia/errno.h
index a269fa3..0c3afb3 100644
--- a/src/shared/include/camellia/errno.h
+++ b/src/shared/include/camellia/errno.h
@@ -2,3 +2,4 @@
 
 #define EFAULT 2
 #define EBADF 3 /* Invalid file descriptor. */
+#define EINVAL 4
diff --git a/src/user/app/init/shell.c b/src/user/app/init/shell.c
index 048b713..a6b9965 100644
--- a/src/user/app/init/shell.c
+++ b/src/user/app/init/shell.c
@@ -1,12 +1,12 @@
 #include "shell.h"
 #include "tests/tests.h"
 #include <camellia/syscalls.h>
+#include <errno.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
 #include <unistd.h>
-#include <user/lib/elfload.h>
 
 static bool isspace(char c) {
 	return c == ' ' || c == '\t' || c == '\n';
@@ -202,14 +202,13 @@ void shell_loop(void) {
 					memcpy(binname + 5, cmd, cmdlen + 1);
 				}
 
-				FILE *file = fopen(binname, "r");
-				if (!file) {
-					printf("unknown command: %s\n", cmd);
+				execv(binname, NULL);
+				if (errno == EINVAL) {
+					printf("%s isn't a valid executable\n", cmd);
 				} else {
-					elf_execf(file);
-					fclose(file);
-					printf("couldn't execute %s\n", binname);
+					printf("unknown command: %s\n", cmd);
 				}
+
 				if (binname != cmd)
 					free(binname);
 			}
diff --git a/src/user/lib/include/unistd.h b/src/user/lib/include/unistd.h
index b825e45..4f367ca 100644
--- a/src/user/lib/include/unistd.h
+++ b/src/user/lib/include/unistd.h
@@ -4,3 +4,5 @@
 int fork(void);
 int close(handle_t h);
 _Noreturn void exit(int);
+
+int execv(const char *path, char *const argv[]);
diff --git a/src/user/lib/stdlib.c b/src/user/lib/stdlib.c
index 068635b..179bd8f 100644
--- a/src/user/lib/stdlib.c
+++ b/src/user/lib/stdlib.c
@@ -1,5 +1,8 @@
 #include <camellia/syscalls.h>
+#include <errno.h>
+#include <stdio.h>
 #include <unistd.h>
+#include <user/lib/elfload.h>
 
 int errno = 0;
 
@@ -14,3 +17,16 @@ int close(handle_t h) {
 _Noreturn void exit(int c) {
 	_syscall_exit(c);
 }
+
+int execv(const char *path, char *const argv[]) {
+	(void)argv;
+
+	FILE *file = fopen(path, "r");
+	if (!file)
+		return -1;
+
+	elf_execf(file);
+	fclose(file);
+	errno = EINVAL;
+	return -1;
+}