1 files changed, 85 insertions, 22 deletions

diff --git a/syscall.jai b/syscall.jai
index 46a9d84..e30dc2f 100644
--- a/syscall.jai
+++ b/syscall.jai
@@ -8,43 +8,106 @@
 // Syscall info: https://filippo.io/linux-syscall-table/
 
 main :: () {
-    print("starting syscall\n");
-
-    sys_exit(-1);
-    fd := sys_open("./dummy");
-    print("fd is %\nerrno is %\n", fd, errno());
     
-    print("done syscall\n");
+    //sys_exit(-1);
+    print("> open dummy\n");
+    fd, error_open := sys_open("./dummy");
+    print("> opened dummy with fd % and errno %\n", fd, error_open);
+    if fd < 0 return;
+    
     LOOPER :: "\\|/-";
     idx := 0;
     loop: string;
     loop.count = 1;
-    for 0..3 {
+    for 0..1 {
         sleep_milliseconds(1000);
         loop.data = *LOOPER.data[idx];
         idx = (idx + 1) % LOOPER.count;
         print("\rlooping %", loop);
     }
+        
+    error_close := sys_close(fd);
+    print("\r> close(%) with errno %\n", fd, error_close);
     
-    sys_close(fd);
-    print("\rclosed\n");
-    
-    for 0..3 {
-        sleep_milliseconds(1000);
-        loop.data = *LOOPER.data[idx];
-        idx = (idx + 1) % LOOPER.count;
-        print("\rlooping %", loop);
-    }
+    print("---\n");
+    error :s64;
+    fd, error = sys_open("./fail");
+    print("$ open(fail) returned fd % and error %\n", fd, error);
+    error = sys_close(456);
+    print("$ close(456) returned error %\n", error);
 }
 
-sys_open :: (path: string) -> fd: s64 {
-    SYS_OPEN :: 2;
-    return syscall(SYS_OPEN, cast(*s8)path.data, O_RDONLY);
+
+
+
+
+
+
+
+sys_open :: (path: string) -> file_descriptor: s64, error: s64 {
+    
+    #if OS == .WINDOWS {
+        print("TODO Implement this\n"); // TODO Implement this.
+    }
+    else #if OS == .LINUX {
+        SYS_OPEN :: 2;
+        data:   *s8 = xx path.data;
+        result: s64 = ---;
+        #if CPU == .X64 {
+            print("\r# LINUX:ASM\n");
+            #asm SYSCALL_SYSRET {
+            mov rax:    gpr === a,  SYS_OPEN;
+            mov rdi:    gpr === di, data;
+            mov rsi:    gpr === si, O_RDONLY;
+            mov rdx:    gpr === d,  O_RDONLY;
+            //syscall rcx, r11, rax, rdi, rsi, rdx; // TODO Cleanup?
+            syscall
+                rcx: gpr === c,     // Implicitly used by syscall to store RIP
+                r11: gpr === 11,    // Implicitly used by syscall to store RFLAGS
+                rax, rdi, rsi, rdx; 
+            mov result, rax;
+            }
+            if result < 0
+                return -1, -result; // Error.
+            else
+                return result, 0; // OK.
+        } else {
+            print("\r# LINUX:LIBC\n");
+            result = syscall(SYS_OPEN, data, O_RDONLY);
+            if result < 0
+                return -1, errno(); // Error.
+            else
+                return result, 0; // OK.
+        }
+    }
 }
 
-sys_close :: (fd: s64) {
-    SYS_CLOSE :: 3;
-    syscall(SYS_CLOSE, fd);
+sys_close :: (file_descriptor: s64) -> error: s64 {
+    
+    #if OS == .WINDOWS {
+        print("TODO Implement this\n"); // TODO Implement this.
+    }
+    else #if OS == .LINUX {
+        SYS_CLOSE :: 3;
+        result: s64 = ---;
+        #if CPU == .X64 {
+            print("\r# LINUX:ASM\n");
+            #asm SYSCALL_SYSRET {
+                mov rax:    gpr === a, SYS_CLOSE;
+                mov rdi:    gpr === di, file_descriptor;
+                syscall
+                    rcx: gpr === c,     // Implicitly used by syscall to store RIP
+                    r11: gpr === 11,    // Implicitly used by syscall to store RFLAGS
+                    rax, rdi;
+                mov result, rax;
+            }
+            return ifx result < 0 then -result else 0;
+        } else {
+            print("\r# LINUX:LIBC\n");
+            result = syscall(SYS_CLOSE, file_descriptor);
+            return ifx result < 0 then errno() else 0;
+        }
+    }
 }
 
 sys_exit :: (status: s32) {