Add getExecutablePath

Author: augustss

generated/mhs.c

@@ -9,6 +9,7 @@ module System.Environment(
   getEnvironment,
   setEnv,
   unsetEnv,
+  getExecutablePath,
   ) where
 import qualified Prelude(); import MiniPrelude
 import Primitives
@@ -17,6 +18,7 @@ import Data.Bifunctor(second)
 import Data.List(span)
 import Foreign.C.Error
 import Foreign.C.String
+import Foreign.Marshal.Alloc
 import Foreign.Marshal.Array
 import Foreign.Ptr
 import System.IO
@@ -95,3 +97,13 @@ unsetEnv key = do
   chkKey "unsetEnv" key
   withCAString key $ \ ckey ->
     throwErrnoIfMinus1_ "unsetEnv" $ c_unsetenv ckey
+
+foreign import ccall get_executable_path :: IO CString
+
+getExecutablePath :: IO String
+getExecutablePath = do
+  p <- throwErrnoIfNull "get_executable_path" get_executable_path
+  s <- peekCAString p
+  free p
+  return s
+

lib/System/Environment.hs

@@ -290,5 +290,6 @@ runtimeFFI = [
   "ETOOMANYREFS", "ETXTBSY", "EUSERS", "EWOULDBLOCK", "EXDEV",
   "errno",
   "strerror_r",
-  "environ"
+  "environ",
+  "get_executable_path"
   ]

src/MicroHs/FFI.hs

@@ -7381,6 +7381,7 @@ from_t mhs_mpz_log2(int s) {
 #if WANT_TIME
 from_t mhs_gettimeofday(int s) { return mhs_from_Int(s, 2, gettimeofday(mhs_to_Ptr(s, 0), mhs_to_Ptr(s, 1))); }
 #endif
+from_t mhs_get_executable_path(int s) { return mhs_from_Ptr(s, 0, get_executable_path()); }
 
 const struct ffi_entry ffi_table[] = {
   { "GETRAW", 0, mhs_GETRAW},
@@ -7687,6 +7688,7 @@ const struct ffi_entry ffi_table[] = {
   { "&errno", 0, mhs_addr_errno},
   { "strerror_r", 3, mhs_strerror_r},
 #endif
+  { "get_executable_path", 0, mhs_get_executable_path},
   { 0,0 }
 };
 

src/runtime/eval.c

@@ -182,3 +182,39 @@ uint64_t end_kperf(void) { return 0; }
 #endif  /* apple-arm */
 
 #endif  /* WANT_KPERF */
+
+#include <stdlib.h>
+
+#if defined(__linux__)
+#include <unistd.h>
+#include <limits.h>
+#elif defined(__APPLE__) && defined(__MACH__)
+#include <mach-o/dyld.h>
+#include <limits.h>
+#endif
+
+/* Return path to executable as a null-terminated UTF-8 string. */
+char*
+get_executable_path(void) {
+#if defined(__linux__)
+    return realpath("/proc/self/exe", NULL);
+
+#elif defined(__APPLE__) && defined(__MACH__)
+    uint32_t size = 0;
+    _NSGetExecutablePath(NULL, &size);
+    char *buf = malloc(size);
+    if (!buf)
+      return NULL;
+
+    if (_NSGetExecutablePath(buf, &size) == 0) {
+        char *canonical = realpath(buf, NULL);
+        free(buf);
+        return canonical;
+    }
+    free(buf);
+    return NULL;
+
+#else  /* Unsupported */
+    return NULL;
+#endif
+}

src/runtime/unix/extra.c

@@ -3,6 +3,8 @@
  */
 #include <conio.h>
 #include <io.h>
+#include <stdlib.h>
+#include <windows.h>
 
 /*
  * Find First Set
@@ -154,3 +156,28 @@ tmpname(const char* prefix, const char* suffix)
   return filename;
 }
 #define TMPNAME tmpname
+
+/* Return path to executable as a null-terminated UTF-8 string. */
+char*
+get_executable_path(void) {
+    DWORD size = MAX_PATH;
+    WCHAR *wbuf = malloc(size * sizeof(WCHAR));
+    if (!wbuf) return NULL;
+
+    DWORD len = GetModuleFileNameW(NULL, wbuf, size);
+    while (len == size && GetLastError() == ERROR_INSUFFICIENT_BUFFER) {
+        size *= 2;
+        WCHAR *new_buf = realloc(wbuf, size * sizeof(WCHAR));
+        if (!new_buf) { free(wbuf); return NULL; }
+        wbuf = new_buf;
+        len = GetModuleFileNameW(NULL, wbuf, size);
+    }
+
+    int utf8_len = WideCharToMultiByte(CP_UTF8, 0, wbuf, -1, NULL, 0, NULL, NULL);
+    char *utf8_buf = malloc(utf8_len);
+    if (utf8_buf) {
+        WideCharToMultiByte(CP_UTF8, 0, wbuf, -1, utf8_buf, utf8_len, NULL, NULL);
+    }
+    free(wbuf);
+    return utf8_buf;
+}