MacOS support (#382)

.github/workflows/linux.yml

@@ -9,7 +9,7 @@ jobs:
     runs-on: ubuntu-latest
     steps:
       - uses: actions/checkout@v3
-      - run: shellcheck --color=always --shell=bash --exclude=SC2086,SC2059,SC2046,SC2235,SC2002,SC2206,SC2068 *.sh activate
+      - run: shellcheck --color=always --shell=bash --exclude=SC2086,SC2059,SC2046,SC2235,SC2002,SC2206,SC2068,SC2207 *.sh activate
 
   test:
     runs-on: ubuntu-latest

.github/workflows/macos.yml

@@ -0,0 +1,34 @@
+on:
+  push:
+    branches:
+      - main
+  pull_request:
+
+jobs:
+  test:
+    runs-on: macos-latest
+    strategy:
+      matrix:
+        # Testing all levels because there was a bug that only happened with -O1. (#224)
+        opt-level: ['-O0', '-O1', '-O2', '-O3']
+    steps:
+      - uses: actions/checkout@v3
+      - run: brew install bash diffutils llvm@13
+      - run: make
+      - run: ./runtests.sh --verbose --jou-flags "${{ matrix.opt-level }}"
+      - run: ./runtests.sh --verbose --jou-flags "${{ matrix.opt-level }} --verbose"
+      - run: make clean
+      - name: Check that "make clean" deleted all files not committed to Git
+        shell: bash
+        run: |
+          if [ "$(git status --porcelain --ignored)" != "" ]; then
+            git status --ignored
+            exit 1
+          fi
+
+  compare-compilers:
+    runs-on: macos-latest
+    steps:
+      - uses: actions/checkout@v3
+      - run: brew install bash diffutils llvm@13
+      - run: ./compare_compilers.sh

Makefile.posix

@@ -1,4 +1,10 @@
-LLVM_CONFIG ?= $(shell which llvm-config-13 || which llvm-config-11)
+# Linux has llvm-config-13, on macos brew installs LLVM to a weird place in /usr/local/
+LLVM_CONFIG ?= $(shell \
+	which llvm-config-13 \
+	|| which /usr/local/opt/llvm@13/bin/llvm-config \
+	|| which llvm-config-11 \
+	|| which /usr/local/opt/llvm@11/bin/llvm-config \
+	)
 CFLAGS += $(shell $(LLVM_CONFIG) --cflags)
 LDFLAGS ?= $(shell $(LLVM_CONFIG) --ldflags --libs)
 
@@ -14,6 +20,7 @@ compile_flags.txt:
 	echo "-I$(shell $(LLVM_CONFIG) --includedir)"  > compile_flags.txt
 
 config.h:
+	@v=`$(LLVM_CONFIG) --version`; case "$$v" in 11.*|13.*) ;; *) echo "Error: Found unsupported LLVM version $$v. Only LLVM 11 and LLVM 13 are supported."; exit 1; esac
 	echo "// auto-generated by Makefile" > config.h
 	echo "#define JOU_CLANG_PATH \"$(shell $(LLVM_CONFIG) --bindir)/clang\"" >> config.h
 
@@ -34,4 +41,4 @@ self_hosted_compiler: jou config.jou $(wildcard self_hosted/*.jou)
 .PHONY: clean
 clean:
 	rm -rvf obj jou jou.exe self_hosted_compiler self_hosted_compiler.exe tmp config.h config.jou compile_flags.txt
-	find -name jou_compiled -print -exec rm -rf '{}' +
+	find . -name jou_compiled -print -exec rm -rf '{}' +

README.md

@@ -107,6 +107,46 @@ $ LLVM_CONFIG=llvm-config-11 make
 
 </details>
 
+<details> <summary>MacOS</summary>
+
+MacOS support is new. Please create an issue if something doesn't work.
+
+1. Install Git, make and LLVM 13.
+    If you do software development on MacOS, you probably already have Git and make,
+    because they come with Xcode Command Line Tools.
+    You can use [brew](https://brew.sh/) to install LLVM 13:
+    ```
+    $ brew install llvm@13
+    ```
+2. Download and compile Jou.
+    ```
+    $ git clone https://github.com/Akuli/jou
+    $ cd jou
+    $ make
+    ```
+3. Run the hello world program to make sure that Jou works:
+    ```
+    $ ./jou examples/hello.jou
+    Hello World
+    ```
+    You can now run other Jou programs in the same way.
+4. (Optional) If you want to run Jou programs with simply `jou filename`
+    instead of something like `./jou filename` or `/full/path/to/jou filename`,
+    you can add the `jou` directory to your PATH.
+    To do so, edit `~/.bashrc` (or whatever other file you have instead, e.g. `~/.zshrc`):
+    ```
+    $ nano ~/.bashrc
+    ```
+    Add the following line to the end:
+    ```
+    export PATH="$PATH:/Users/yourname/jou/"
+    ```
+    Replace `/Users/yourname/jou/` with the path to the folder (not the executable file) where you downloaded Jou.
+    Note that the `~` character does not work here,
+    so you need to use a full path (or `$HOME`) instead.
+
+</details>
+
 <details> <summary>64-bit Windows</summary>
 
 1. Go to releases on GitHub. It's in the sidebar at right.

compare_compilers.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 # There are two Jou compilers: one written in C and another written in Jou.
 # They should be able to tokenize and parse each Jou file in exactly the same way.
@@ -29,7 +29,7 @@ done
 
 if [ ${#files[@]} = 0 ]; then
     # TODO: do not skip Advent Of Code files
-    mapfile -t files < <( find stdlib examples tests -name '*.jou' | grep -v aoc2023 | sort )
+    files=( $(find stdlib examples tests -name '*.jou' | grep -v aoc2023 | sort) )
 fi
 if [ ${#actions[@]} = 0 ]; then
     actions=(tokenize parse run)

runtests.sh

@@ -1,4 +1,4 @@
-#!/bin/bash
+#!/usr/bin/env bash
 #
 #
 #
@@ -119,8 +119,9 @@ function post_process_output()
         echo "A lot of output hidden..."
         grep "^Exit code:"
     elif [[ $joufile =~ ^tests/crash/ ]]; then
-        if [[ "$OS" =~ Windows ]]; then
-            # Windows doesn't say "Segmentation fault" when a program crashes
+        if [ "$(uname -s)" != Linux ]; then
+            # Windows and macos don't seem to say "Segmentation fault" when
+            # a program crashes
             echo "Segmentation fault"
         fi
         # Hide most of the output. We really only care about whether it

self_hosted/paths.jou

@@ -9,31 +9,83 @@ declare _mkdir(path: byte*) -> int  # windows
 declare mkdir(path: byte*, mode: int) -> int  # posix
 declare dirname(path: byte*) -> byte*
 declare stat(path: byte*, buf: byte[1000]*) -> int  # lol
+declare popen(command: byte*, type: byte*) -> FILE*
+declare pclose(stream: FILE*) -> int
+declare _NSGetExecutablePath(buf: byte*, bufsize: int*) -> int
+
 
 def is_windows() -> bool:
     # TODO: this is just weird...
     return getenv("OS") != NULL and strstr(getenv("OS"), "Windows") != NULL
 
-# Return a path to the currently running program. Return value must be free()d.
-def find_current_executable() -> byte*:
+# https://stackoverflow.com/a/3466183
+def is_macos() -> bool:
+    if is_windows():
+        return False
+
+    uname = popen("uname", "r")
+    if uname == NULL:
+        return False
+
+    output: byte[100]
+    memset(&output, 0, sizeof(output))
+    fgets(output, sizeof(output) as int, uname)
+
+    pclose(uname)
+    return starts_with(output, "Darwin")
+
+
+def _find_current_executable_windows() -> byte*:
     buf = NULL
     for size = 2L; True; size *= 2:
         buf = realloc(buf, size)
         memset(buf, 0, size)
+        ret = GetModuleFileNameA(NULL, buf, size as int)
+        if ret <= 0:
+            return NULL  # error --> give up
+        if ret < size:
+            # buffer is big enough, it fits
+            return buf
 
-        if is_windows():
-            ret: long = GetModuleFileNameA(NULL, buf, size as int)
-        else:
-            ret = readlink("/proc/self/exe", buf, size)
+def _find_current_executable_macos() -> byte*:
+    n = 1
+    result: byte* = malloc(n)
+    ret = _NSGetExecutablePath(result, &n)  # sets n to desired size
+    assert ret < 0  # didn't fit
+    result = realloc(result, n)
+    ret = _NSGetExecutablePath(result, &n)
+    assert ret == 0
+    return result
 
+def _find_current_executable_linux() -> byte*:
+    buf = NULL
+    for size = 2L; True; size *= 2:
+        buf = realloc(buf, size)
+        memset(buf, 0, size)
+        ret = readlink("/proc/self/exe", buf, size)
         if ret <= 0:
-            # TODO: include os error message (GetLastError / errno)
-            fprintf(stderr, "error: cannot locate currently running executable, needed for finding the Jou standard library\n")
-            exit(1)
+            return NULL
         if ret < size:
             # buffer is big enough, it fits
             return buf
 
+
+def find_current_executable() -> byte*:
+    if is_windows():
+        result = _find_current_executable_windows()
+    elif is_macos():
+        result = _find_current_executable_macos()
+    else:
+        result = _find_current_executable_linux()
+
+    if result == NULL:
+        # TODO: include os error message (GetLastError / errno)
+        fprintf(stderr, "error: cannot locate currently running executable, needed for finding the Jou standard library\n")
+        exit(1)
+
+    return result
+
+
 def find_installation_directory() -> byte*:
     exe = find_current_executable()
     result = strdup(dirname(exe))

self_hosted/runs_wrong.txt

@@ -44,3 +44,4 @@ tests/wrong_type/cannot_be_indexed.jou
 tests/wrong_type/index.jou
 stdlib/ascii.jou
 tests/should_succeed/ascii_test.jou
+stdlib/_macos_startup.jou

src/codegen.c

@@ -190,9 +190,11 @@ static LLVMValueRef codegen_function_or_method_decl(const struct State *st, cons
     // make it a definition instead of a declaration so that there are no linker errors.
     // Ideally it would be possible to compile some parts of Jou code only for a specific platform.
 #ifdef _WIN32
-    const char *doesnt_exist[] = { "readlink", "mkdir" };
-#else
+    const char *doesnt_exist[] = { "readlink", "mkdir", "popen", "pclose", "_NSGetExecutablePath" };
+#elif defined(__APPLE__)
     const char *doesnt_exist[] = { "GetModuleFileNameA", "_mkdir" };
+#else
+    const char *doesnt_exist[] = { "GetModuleFileNameA", "_mkdir", "_NSGetExecutablePath" };
 #endif
     for (unsigned i = 0; i < sizeof doesnt_exist / sizeof doesnt_exist[0]; i++) {
         if (!strcmp(fullname, doesnt_exist[i])) {
@@ -434,11 +436,18 @@ static int find_block(const CfGraph *cfg, const CfBlock *b)
     assert(0);
 }
 
-#ifdef _WIN32
+#if defined(_WIN32) || defined(__APPLE__)
 static void codegen_call_to_the_special_startup_function(const struct State *st)
 {
+    const char *name;
+#ifdef _WIN32
+    name = "_jou_windows_startup";
+#else
+    name = "_jou_macos_startup";
+#endif
+
     LLVMTypeRef functype = LLVMFunctionType(LLVMVoidType(), NULL, 0, false);
-    LLVMValueRef func = LLVMAddFunction(st->module, "_jou_windows_startup", functype);
+    LLVMValueRef func = LLVMAddFunction(st->module, name, functype);
     LLVMBuildCall2(st->builder, functype, func, NULL, 0, "");
 }
 #endif
@@ -461,7 +470,7 @@ static void codegen_function_or_method_def(struct State *st, const CfGraph *cfg)
     assert(cfg->all_blocks.ptr[0] == &cfg->start_block);
     LLVMPositionBuilderAtEnd(st->builder, blocks[0]);
 
-#ifdef _WIN32
+#if defined(_WIN32) || defined(__APPLE__)
     if (!get_self_class(&cfg->signature) && !strcmp(cfg->signature.name, "main"))
         codegen_call_to_the_special_startup_function(st);
 #endif

src/main.c

@@ -453,6 +453,9 @@ int main(int argc, char **argv)
 #ifdef _WIN32
     include_special_stdlib_file(&compst, "_windows_startup.jou");
 #endif
+#ifdef __APPLE__
+    include_special_stdlib_file(&compst, "_macos_startup.jou");
+#endif
 
     parse_file(&compst, command_line_args.infile, NULL);
     parse_all_pending_files(&compst);

src/util.c

@@ -2,11 +2,17 @@
     // readlink() stuff
     #define _POSIX_C_SOURCE 200112L
     #include <unistd.h>
-#endif // _WIN32
+#endif
+
+#ifdef __APPLE__
+    #include <mach-o/dyld.h>  // _NSGetExecutablePath
+#endif
 
 #include "util.h"
 #include <ctype.h>
 #include <errno.h>
+#include <stdbool.h>
+#include <stdnoreturn.h>
 #include <stdio.h>
 #include <stdlib.h>
 
@@ -58,28 +64,31 @@ void simplify_path(char *path)
 // argv[0] doesn't work as expected when Jou is ran through PATH.
 char *find_current_executable(void)
 {
-    char *result;
-    const char *err;
+    char *result = NULL;
+    const char *err = NULL;
 
 #ifdef _WIN32
     extern char *_pgmptr;  // A documented global variable in Windows. Full path to executable.
     result = strdup(_pgmptr);
-    err = NULL;
+#elif defined(__APPLE__)
+    uint32_t n = 1;
+    result = malloc(n);
+    int ret = _NSGetExecutablePath(result, &n);  // sets n to desired size
+    assert(ret < 0);  // didn't fit
+    result = realloc(result, n);
+    ret = _NSGetExecutablePath(result, &n);
+    assert(ret == 0);
 #else
-    int n = 10000;
-    result = calloc(1, n);
-    ssize_t ret = readlink("/proc/self/exe", result, n);
-
-    if (ret < 0)
+    ssize_t ret;
+    int n = 1;
+    do {
+        n *= 2;
+        result = realloc(result, n);
+        memset(result, 0, n);  // readlink() doesn't nul terminate
+        ret = readlink("/proc/self/exe", result, n);
+    } while (ret == n);
+    if (ret<0)
         err = strerror(errno);
-    else if (ret == n) {
-        static char s[100];
-        sprintf(s, "path is more than %d bytes long", n);
-        err=s;
-    } else {
-        assert(0<ret && ret<n);
-        err = NULL;
-    }
 #endif
 
     if(err) {

stdlib/_macos_startup.jou

@@ -0,0 +1,26 @@
+# A call to the _jou_macos_startup() function is inserted to the
+# start of every Jou program when compiling for MacOS.
+
+# On macos, the C "global variables" stdin, stdout and stderr have
+# different names. For simplicity, Jou redefines them as variables
+# with the same names and assigns the correct values to them.
+#
+# We can't import FILE from io.jou here, because then we would be
+# trying to define a variable that already exists.
+global stdin: void*
+global stdout: void*
+global stderr: void*
+declare global __stdinp: void*
+declare global __stdoutp: void*
+declare global __stderrp: void*
+
+def _jou_macos_startup() -> void:
+    stdin = __stdinp
+    stdout = __stdoutp
+    stderr = __stderrp
+
+# On linux, C's errno is a macro that expands to (*__errno_location()).
+# On macos it expands to (*__error()) instead. Let's make it consistent.
+declare __error() -> int*
+def __errno_location() -> int*:
+    return __error()