From 386ed4b75026f1262818ae5631eb593e694f2185 Mon Sep 17 00:00:00 2001
From: "Nahuel J. Sacchetti" <me@nsacchetti.com>
Date: Wed, 16 Oct 2024 14:15:53 -0500
Subject: [PATCH] feat: add namespacing for foreign and unit tests for C
 interoperability

---
 compiler/codegen.go  | 15 ++++++++++-----
 compiler/frontend.go | 14 +++++++++++++-
 libs/libc.sk         |  8 +++++---
 tests/c-printf.sk    |  6 ++++++
 tests/c-printf.txt   |  1 +
 5 files changed, 35 insertions(+), 9 deletions(-)
 create mode 100644 tests/c-printf.sk
 create mode 100644 tests/c-printf.txt

diff --git a/compiler/codegen.go b/compiler/codegen.go
index 9fd075d..4110ed5 100644
--- a/compiler/codegen.go
+++ b/compiler/codegen.go
@@ -58,7 +58,7 @@ func generateLinuxX64() {
 		out.WriteMetadata("public main")
 		for _, f := range TheProgram.chunks {
 			if f.foreign {
-				out.WriteMetadata("extrn %s", f.word)
+				out.WriteMetadata("extrn %s", f.name)
 			}
 		}
 		out.WriteCode("section '.text' executable")
@@ -307,7 +307,7 @@ func generateLinuxX64() {
 					out.WriteCode("    pop %s", registers[i])
 				}
 
-				out.WriteCode("    call %s", function.word)
+				out.WriteCode("    call %s", function.name)
 
 				if hasResults {
 					out.WriteCode("    push rax")
@@ -367,9 +367,14 @@ func generateLinuxX64() {
 	out.WriteCode("    mov rax, return_stack_rsp_end")
 	out.WriteCode("    mov [return_stack_rsp], rax")
 	out.WriteCode("    call fn%d", mainFuncIP)
-	out.WriteCode("    mov rax, 60")
-	out.WriteCode("    mov rdi, 0")
-	out.WriteCode("    syscall")
+	if TheProgram.libcEnabled {
+		out.WriteCode("    mov rdi, 0")
+		out.WriteCode("    call exit")
+	} else {
+		out.WriteCode("    mov rax, 60")
+		out.WriteCode("    mov rdi, 0")
+		out.WriteCode("    syscall")
+	}
 }
 
 func CodegenRun(out *OutputCode) {
diff --git a/compiler/frontend.go b/compiler/frontend.go
index c2e2bee..14f10bf 100644
--- a/compiler/frontend.go
+++ b/compiler/frontend.go
@@ -22,6 +22,8 @@ const (
 type Function struct {
 	ip              int
 	loc             Location
+	name            string
+	namespace       string
 	token           Token
 	word            string
 
@@ -373,6 +375,14 @@ func createConstant() {
 func createForeigns() {
 	t := parser.previousToken
 
+	if !match(TOKEN_WORD) {
+		t := parser.previousToken
+		ReportErrorAtLocation(DeclarationWordMissing, t.loc)
+		ExitWithError(ParseError)
+	}
+
+	namespace := parser.previousToken.value.(string)
+
 	consume(TOKEN_CURLY_BRACKET_OPEN,
 		UnexpectedSymbol, parser.previousToken.kind, "{")
 
@@ -392,7 +402,9 @@ func createForeigns() {
 			advance()
 
 			tokenWord := parser.previousToken
-			function.word = tokenWord.value.(string)
+			function.namespace = namespace
+			function.name = tokenWord.value.(string)
+			function.word = function.namespace + "." + function.name
 			consume(TOKEN_PAREN_OPEN, UnexpectedSymbol, t.kind, "(")
 			parsingArguments := true
 
diff --git a/libs/libc.sk b/libs/libc.sk
index 7207dc0..03729c7 100644
--- a/libs/libc.sk
+++ b/libs/libc.sk
@@ -34,7 +34,9 @@
 ; all the C required procedures, making compilation slower and final file
 ; size bigger. 'libc' is linked statically.
 
-foreign {
-  fn printf (any str) ...
-  fn puts   (str)     ...
+foreign c {
+  fn exit    (int)         ...
+  fn fprintf (int any str) ...
+  fn printf  (any str)     ...
+  fn puts    (str)         ...
 }
diff --git a/tests/c-printf.sk b/tests/c-printf.sk
new file mode 100644
index 0000000..3e26439
--- /dev/null
+++ b/tests/c-printf.sk
@@ -0,0 +1,6 @@
+using libc
+using unix
+
+fn main ()
+  "Stańczyk" "Hello, %s\n" c.printf
+ret
diff --git a/tests/c-printf.txt b/tests/c-printf.txt
new file mode 100644
index 0000000..18c53b6
--- /dev/null
+++ b/tests/c-printf.txt
@@ -0,0 +1 @@
+Hello, Stańczyk