Make function stubs in libc loudly abort instead of silently failing

apps/src/init.c

@@ -1,3 +1,4 @@
+#include <luna.h>
 #include <stdlib.h>
 #include <string.h>
 #include <sys/syscall.h>
@@ -12,7 +13,7 @@ static void print(const char* message)
 
 int main()
 {
-    if (syscall(SYS_gettid) == 0) // why are we the idle task?
+    if (gettid() == 0) // why are we the idle task?
     {
         println("SHENANIGANS! init is tid 0 (which is reserved for the idle task)");
         abort();
@@ -21,7 +22,7 @@ int main()
     println("Welcome to Luna from a C init!");
     println("");
 
-    syscall(SYS_sleep, 1000);
+    sleep(1);
 
     print("Your kernel version is ");
 
@@ -31,7 +32,7 @@ int main()
     print(version);
     println("\n");
 
-    syscall(SYS_sleep, 2000);
+    sleep(2);
 
     println("Press any key to restart.");
 

libs/libc/include/luna.h

@@ -0,0 +1,23 @@
+#ifndef _LUNA_H
+#define _LUNA_H
+
+#include <sys/types.h>
+
+#define noreturn __attribute__((noreturn))
+
+#ifdef __cplusplus
+extern "C"
+{
+#endif
+
+    pid_t gettid();
+    unsigned int msleep(unsigned int);
+    noreturn void __luna_abort(const char* message);
+
+#ifdef __cplusplus
+}
+#endif
+
+#define NOT_IMPLEMENTED(message) __luna_abort("not implemented: " message "\n")
+
+#endif

libs/libc/include/unistd.h

@@ -10,6 +10,7 @@ extern "C"
     int execvp(const char*, char* const[]);
     pid_t fork(void);
     long syscall(long, ...);
+    unsigned int sleep(unsigned int);
 
 #ifdef __cplusplus
 }

libs/libc/src/luna.cpp

@@ -0,0 +1,26 @@
+#include <luna.h>
+#include <string.h>
+#include <sys/syscall.h>
+#include <unistd.h>
+
+#define noreturn __attribute__((noreturn))
+
+extern "C"
+{
+    pid_t gettid()
+    {
+        return syscall(SYS_gettid);
+    }
+
+    unsigned int msleep(unsigned int ms)
+    {
+        return syscall(SYS_sleep, ms);
+    }
+
+    noreturn void __luna_abort(const char* message)
+    {
+        syscall(SYS_write, message, strlen(message));
+        syscall(SYS_exit);
+        __builtin_unreachable();
+    }
+}

libs/libc/src/stdio.cpp

@@ -1,45 +1,46 @@
+#include <luna.h>
 #include <stdio.h>
 
 extern "C"
 {
     int fclose(FILE*)
     {
-        return -1;
+        NOT_IMPLEMENTED("fclose");
     }
     int fflush(FILE*)
     {
-        return -1;
+        NOT_IMPLEMENTED("fflush");
     }
     FILE* fopen(const char*, const char*)
     {
-        return 0;
+        NOT_IMPLEMENTED("fopen");
     }
     int fprintf(FILE*, const char*, ...)
     {
-        return -1;
+        NOT_IMPLEMENTED("fprintf");
     }
     size_t fread(void*, size_t, size_t, FILE*)
     {
-        return 0;
+        NOT_IMPLEMENTED("fread");
     }
     int fseek(FILE*, long, int)
     {
-        return -1;
+        NOT_IMPLEMENTED("fseek");
     }
     long ftell(FILE*)
     {
-        return -1;
+        NOT_IMPLEMENTED("ftell");
     }
     size_t fwrite(const void*, size_t, size_t, FILE*)
     {
-        return 0;
+        NOT_IMPLEMENTED("fwrite");
     }
     void setbuf(FILE*, char*)
     {
-        return;
+        NOT_IMPLEMENTED("setbuf");
     }
     int vfprintf(FILE*, const char*, va_list)
     {
-        return -1;
+        NOT_IMPLEMENTED("vfprintf");
     }
 }

libs/libc/src/stdlib.cpp

@@ -1,3 +1,4 @@
+#include <luna.h>
 #include <stdlib.h>
 #include <sys/syscall.h>
 #include <unistd.h>
@@ -22,22 +23,22 @@ extern "C"
 
     int atexit(void (*)(void))
     {
-        return -1;
+        NOT_IMPLEMENTED("atexit");
     }
     int atoi(const char*)
     {
-        return 0;
+        NOT_IMPLEMENTED("atoi");
     }
     void free(void*)
     {
-        return;
+        NOT_IMPLEMENTED("free");
     }
     char* getenv(const char*)
     {
-        return 0;
+        NOT_IMPLEMENTED("getenv");
     }
     void* malloc(size_t)
     {
-        return 0;
+        NOT_IMPLEMENTED("malloc");
     }
 }

libs/libc/src/string.cpp

@@ -1,3 +1,4 @@
+#include <luna.h>
 #include <string.h>
 
 extern "C"
@@ -42,6 +43,6 @@ extern "C"
 
     char* strchr(const char*, int)
     {
-        return 0;
+        NOT_IMPLEMENTED("strchr");
     }
 }

libs/libc/src/unistd.cpp

@@ -1,3 +1,4 @@
+#include <luna.h>
 #include <luna/syscall.h>
 #include <stdarg.h>
 #include <unistd.h>
@@ -6,19 +7,19 @@ extern "C"
 {
     int execv(const char*, char* const[])
     {
-        return -1;
+        NOT_IMPLEMENTED("execv");
     }
     int execve(const char*, char* const[], char* const[])
     {
-        return -1;
+        NOT_IMPLEMENTED("execve");
     }
     int execvp(const char*, char* const[])
     {
-        return -1;
+        NOT_IMPLEMENTED("execvp");
     }
     pid_t fork(void)
     {
-        return -1;
+        NOT_IMPLEMENTED("fork");
     }
 
     long syscall(long number, ...)
@@ -55,4 +56,9 @@ extern "C"
         va_end(ap);
         return result;
     }
+
+    unsigned int sleep(unsigned int seconds)
+    {
+        return msleep(seconds * 1000);
+    }
 }