From 531afc3d6f6a2432bc1b04d281c8aa8186d8c476 Mon Sep 17 00:00:00 2001
From: apio <blobs.trading@gmail.com>
Date: Wed, 12 Oct 2022 17:45:58 +0200
Subject: [PATCH] libc: Add support for the new exec() system call

execv() is a temporary wrapper that ignores the second parameter, while execve() and execvp() still error out.
---
 kernel/src/sys/Syscall.cpp       | 2 +-
 libs/libc/include/luna/syscall.h | 1 +
 libs/libc/include/unistd.h       | 6 ++++--
 libs/libc/src/unistd.cpp         | 5 +++--
 4 files changed, 9 insertions(+), 5 deletions(-)

diff --git a/kernel/src/sys/Syscall.cpp b/kernel/src/sys/Syscall.cpp
index 5c3a21e6..8a3434b9 100644
--- a/kernel/src/sys/Syscall.cpp
+++ b/kernel/src/sys/Syscall.cpp
@@ -21,7 +21,7 @@ void Syscall::entry(Context* context)
     case SYS_read: sys_read(context, (int)context->rdi, context->rsi, (char*)context->rdx); break;
     case SYS_close: sys_close(context, (int)context->rdi); break;
     case SYS_seek: sys_seek(context, (int)context->rdi, (long)context->rsi, (int)context->rdx); break;
-    case SYS_exec: sys_exec(context, (const char*)context->rdi);
+    case SYS_exec: sys_exec(context, (const char*)context->rdi); break;
     default: context->rax = -ENOSYS; break;
     }
 }
\ No newline at end of file
diff --git a/libs/libc/include/luna/syscall.h b/libs/libc/include/luna/syscall.h
index 21e3fb47..cc0c24ce 100644
--- a/libs/libc/include/luna/syscall.h
+++ b/libs/libc/include/luna/syscall.h
@@ -14,6 +14,7 @@
 #define SYS_read 10
 #define SYS_close 11
 #define SYS_seek 12
+#define SYS_exec 13
 
 #ifndef __want_syscalls
 #ifdef __cplusplus
diff --git a/libs/libc/include/unistd.h b/libs/libc/include/unistd.h
index 5a029030..871b3646 100644
--- a/libs/libc/include/unistd.h
+++ b/libs/libc/include/unistd.h
@@ -9,8 +9,10 @@ extern "C"
 {
 #endif
 
-    /* Not implemented. */
-    int execv(const char*, char* const[]);
+    /* Executes the program program. On success, does not return. The second parameter (arguments) is not implemented
+     * for now. You can pass NULL to it. */
+    int execv(const char* program, char* const[]);
+
     /* Not implemented. */
     int execve(const char*, char* const[], char* const[]);
     /* Not implemented. */
diff --git a/libs/libc/src/unistd.cpp b/libs/libc/src/unistd.cpp
index 0cd572f6..8b1da12e 100644
--- a/libs/libc/src/unistd.cpp
+++ b/libs/libc/src/unistd.cpp
@@ -6,9 +6,9 @@
 
 extern "C"
 {
-    int execv(const char*, char* const[])
+    int execv(const char* program, char* const[])
     {
-        NOT_IMPLEMENTED("execv");
+        return (int)syscall(SYS_exec, program);
     }
     int execve(const char*, char* const[], char* const[])
     {
@@ -36,6 +36,7 @@ extern "C"
         case SYS_rand: result = __luna_syscall0(number); break;
         case SYS_exit:
         case SYS_close:
+        case SYS_exec:
         case SYS_sleep: result = __luna_syscall1(number, va_arg(ap, arg)); break;
         case SYS_munmap:
         case SYS_open: {