implement our own readdir and strtol, syscall builtin

src/codegen_x86_64.rs

@@ -106,7 +106,7 @@ section .text
         );
 
         // take that rustfmt
-        for name in "syscall,malloc,realloc,free,snprintf,strtol,system,opendir,readdir,closedir,gettimeofday,send,write,read,close,getchar,gethostbyname".split(",")
+        for name in "malloc,realloc,free,snprintf,system,gettimeofday,send,write,read,close,getchar,gethostbyname".split(",")
         {
             emit!(&mut self.output, "extern {}", name);
             emit!(&mut self.output, "c.{} equ {}", name, name);
@@ -121,6 +121,12 @@ _builtin_read8:
     mov al, byte [rdi]
     ret
 
+section .text._builtin_read16
+_builtin_read16:
+    xor rax, rax
+    mov ax, word [rdi]
+    ret
+
 section .text._builtin_read32
 _builtin_read32:
     mov eax, dword [rdi]
@@ -140,6 +146,18 @@ section .text._builtin_set64
 _builtin_set64:
     mov [rdi], rsi
     ret
+
+section .text._builtin_syscall
+_builtin_syscall:
+    mov rax, rdi
+    mov rdi, rsi
+    mov rsi, rdx
+    mov rdx, rcx
+    mov r10, r8
+    mov r8,  r9
+    mov r9,  [rsp+8]
+    syscall
+    ret
 "
         );
         Ok(())

src/std.zr

@@ -16,6 +16,9 @@ func mem.zero[x: I64, size: I64] : Void
 func mem.read8[x: Ptr] : U8
     return _builtin_read8(x)
 
+func mem.read16[x: Ptr] : I64
+    return _builtin_read16(x)
+
 func mem.read32[x: Ptr] : I64
     return _builtin_read32(x)
 
@@ -29,7 +32,7 @@ func mem.write64[x: Ptr, d: I64] : Void
     _builtin_set64(x, d)
 
 func io.print[x: String] : Void
-    c.syscall(1, 1, x, str.len(x))
+    _builtin_syscall(1, 1, x, str.len(x))
 
 func io.println[x: String] : Void
     io.print(x)
@@ -38,7 +41,7 @@ func io.println[x: String] : Void
 func io.print_char[x: U8] : Void
     let s: String = mem.alloc(1)
     str.set(s, 0, x)
-    c.syscall(1, 1, s, 1)
+    _builtin_syscall(1, 1, s, 1)
     mem.free(s)
 
 func io.print_i64[x: I64] : Void
@@ -53,33 +56,33 @@ func io.println_i64[x: I64] : Void
 
 func io.read_stdin[]: String
     let buffer: String = mem.alloc(1025)
-    let n: I64 = c.syscall(0, 0, buffer, 1024)
+    let n: I64 = _builtin_syscall(0, 0, buffer, 1024)
     if n < 0
         return ""
     str.set(buffer, n, 0)
     return buffer
 
 func io.read_file[path: String]: String
-    let fd: I64 = c.syscall(2, path, 0, 0) // open
+    let fd: I64 = _builtin_syscall(2, path, 0, 0) // open
     if fd <= 0
         dbg.panic("failed to open file")
 
-    let size: I64 = c.syscall(8, fd, 0, 2) // lseek to the end
-    c.syscall(8, fd, 0, 0) // lseek back to start
+    let size: I64 = _builtin_syscall(8, fd, 0, 2) // lseek to the end
+    _builtin_syscall(8, fd, 0, 0) // lseek back to start
 
     let buffer: String = mem.alloc(size + 1)
-    let n: I64 = c.syscall(0, fd, buffer, size) // read
+    let n: I64 = _builtin_syscall(0, fd, buffer, size) // read
     str.set(buffer, n, 0)
-    c.syscall(3, fd) // close
+    _builtin_syscall(3, fd) // close
     return buffer
 
 func io.write_file[path: String, content: String] : Void
-    let fd: Ptr = c.syscall(2, path, 0x241, 0o644) // open
+    let fd: Ptr = _builtin_syscall(2, path, 0x241, 0o644) // open
     if fd < 0
         dbg.panic("failed to open file")
 
-    c.syscall(1, fd, content, str.len(content)) // write
-    c.syscall(3, fd) // close
+    _builtin_syscall(1, fd, content, str.len(content)) // write
+    _builtin_syscall(3, fd) // close
 
 func str.len[s: String] : I64
     let i: I64 = 0
@@ -195,7 +198,22 @@ func str.from_i64[n: I64] : String
     return x
 
 func str.parse_i64[s: String] : I64
-    return c.strtol(s, 0, 0)
+    let len: I64 = str.len(s)
+    let i: I64 = 0
+
+    let sign: I64 = 1
+    if i < len & s[i] == '-'
+        sign = -1
+        i = i + 1
+
+    let num: I64 = 0
+    while i < len
+        let d: U8 = s[i]
+        if d < '0' | d > '9'
+            break
+        num = num * 10 + (d - '0')
+        i = i + 1
+    return num * sign
 
 func str.hex_encode[s: String] : String
     let hex_chars: String = "0123456789abcdef"
@@ -297,9 +315,9 @@ func math.is_prime[n: I64]: Bool
 
 func math.urandom[]: I64
     let buffer: Ptr = mem.alloc(8)
-    let fd: I64 = c.syscall(2, "/dev/urandom", 0, 0) // open
-    c.syscall(0, fd, buffer, 8) // read
-    c.syscall(3, fd) // close
+    let fd: I64 = _builtin_syscall(2, "/dev/urandom", 0, 0) // open
+    _builtin_syscall(0, fd, buffer, 8) // read
+    _builtin_syscall(3, fd) // close
     let n: I64 = mem.read64(buffer)
     mem.free(buffer)
     return n
@@ -370,7 +388,7 @@ func alg._partition[arr: Array, low: I64, high: I64] : I64
     return i + 1
 
 func os.exit[code: I64] : Void
-    c.syscall(60, code)
+    _builtin_syscall(60, code)
 
 func os.time[] : I64
     let tv: Ptr = mem.alloc(16)
@@ -381,29 +399,40 @@ func os.time[] : I64
     return seconds * 1000 + microseconds / 1000
 
 func os.listdir[path: String] : Array
-    let dir: Ptr = c.opendir(path)
-    let files: Array = []
+    let fd: I64 = _builtin_syscall(2, path, 0, 0) // open
+    if fd < 0
+        return []
 
+    let files: Array = []
+    let buf: Ptr = mem.alloc(1024)
     while true
-        let entry: Ptr = c.readdir(dir)
-        if entry == 0
+        let n: I64 = _builtin_syscall(217, fd, buf, 1024) // getdents64
+        if n <= 0
             break
 
-        let skip: Bool = false
-        if entry[19] == '.'
-            if entry[20] == 0
-                skip = true
-            else if entry[20] == '.'
-                if entry[21] == 0
-                    skip = true
+        let pos: I64 = 0
+        while pos < n
+            let len: I64 = mem.read16(buf + pos + 16)
+            let name: String = buf + pos + 19
+            if name[0]
+                let skip: Bool = false
+                // skip if name is exactly '.' or '..'
+                if name[0] == '.'
+                    if name[1] == 0
+                        skip = true
+                    else if name[1] == '.'
+                        if name[2] == 0
+                            skip = true
+                if !skip
+                    array.push(files, str.copy(name))
+            pos = pos + len
 
-        if !skip
-            array.push(files, str.copy(entry + 19))
-    c.closedir(dir)
+    mem.free(buf)
+    _builtin_syscall(3, fd) // close
     return files
 
 func net.listen[port: I64] : I64
-    let s: I64 = c.syscall(41, 2, 1, 0) // socket
+    let s: I64 = _builtin_syscall(41, 2, 1, 0) // socket
     if s < 0
         return -1
 
@@ -414,13 +443,13 @@ func net.listen[port: I64] : I64
     mem.write8(sa + 2, (port >> 8) & 255)
     mem.write8(sa + 3, port & 255)
 
-    if c.syscall(49, s, sa, 16) < 0 // bind
-        c.syscall(3, s) // close
+    if _builtin_syscall(49, s, sa, 16) < 0 // bind
+        _builtin_syscall(3, s) // close
         return -1
     mem.free(sa)
 
-    if c.syscall(50, s, 1) < 0 // listen
-        c.syscall(3, s) // close
+    if _builtin_syscall(50, s, 1) < 0 // listen
+        _builtin_syscall(3, s) // close
         return -1
     
     return s
@@ -432,7 +461,7 @@ func net.connect[host: String, port: I64] : I64
 
     let ip_ptr: Ptr = mem.read64(mem.read64(he + 24))
 
-    let s: I64 = c.syscall(41, 2, 1, 0) // socket
+    let s: I64 = _builtin_syscall(41, 2, 1, 0) // socket
     if s < 0
         return -1
 
@@ -446,9 +475,9 @@ func net.connect[host: String, port: I64] : I64
     mem.write8(sa + 6, ip_ptr[2])
     mem.write8(sa + 7, ip_ptr[3])
 
-    if c.syscall(42, s, sa, 16) < 0 // connect
+    if _builtin_syscall(42, s, sa, 16) < 0 // connect
         mem.free(sa)
-        c.syscall(3, s) // close
+        _builtin_syscall(3, s) // close
         return -1
 
     mem.free(sa)