1 files changed, 88 insertions, 23 deletions

diff --git a/llvm/lib/Support/Unix/Path.inc b/llvm/lib/Support/Unix/Path.inc
index 2a03dc682bced..d91b269cc6d33 100644
--- a/llvm/lib/Support/Unix/Path.inc
+++ b/llvm/lib/Support/Unix/Path.inc
@@ -48,6 +48,8 @@ extern char **environ;
 #endif
 #elif defined(__DragonFly__)
 #include <sys/mount.h>
+#elif defined(__MVS__)
+#include <sys/ps.h>
 #endif
 
 // Both stdio.h and cstdio are included via different paths and
@@ -56,10 +58,13 @@ extern char **environ;
 #undef ferror
 #undef feof
 
+#if !defined(PATH_MAX)
 // For GNU Hurd
-#if defined(__GNU__) && !defined(PATH_MAX)
-# define PATH_MAX 4096
-# define MAXPATHLEN 4096
+#if defined(__GNU__)
+#define PATH_MAX 4096
+#elif defined(__MVS__)
+#define PATH_MAX _XOPEN_PATH_MAX
+#endif
 #endif
 
 #include <sys/types.h>
@@ -101,7 +106,8 @@ typedef uint_t uint;
 #define STATVFS_F_FRSIZE(vfs) static_cast<uint64_t>(vfs.f_bsize)
 #endif
 
-#if defined(__NetBSD__) || defined(__DragonFly__) || defined(__GNU__)
+#if defined(__NetBSD__) || defined(__DragonFly__) || defined(__GNU__) || \
+    defined(__MVS__)
 #define STATVFS_F_FLAG(vfs) (vfs).f_flag
 #else
 #define STATVFS_F_FLAG(vfs) (vfs).f_flags
@@ -184,10 +190,10 @@ std::string getMainExecutable(const char *argv0, void *MainAddr) {
   // On OS X the executable path is saved to the stack by dyld. Reading it
   // from there is much faster than calling dladdr, especially for large
   // binaries with symbols.
-  char exe_path[MAXPATHLEN];
+  char exe_path[PATH_MAX];
   uint32_t size = sizeof(exe_path);
   if (_NSGetExecutablePath(exe_path, &size) == 0) {
-    char link_path[MAXPATHLEN];
+    char link_path[PATH_MAX];
     if (realpath(exe_path, link_path))
       return link_path;
   }
@@ -208,14 +214,9 @@ std::string getMainExecutable(const char *argv0, void *MainAddr) {
   while (*p++ != 0)
     ;
   // Iterate through auxiliary vectors for AT_EXECPATH.
-  for (;;) {
-    switch (*(uintptr_t *)p++) {
-    case AT_EXECPATH:
+  for (; *(uintptr_t *)p != AT_NULL; p++) {
+    if (*(uintptr_t *)p++ == AT_EXECPATH)
       return *p;
-    case AT_NULL:
-      break;
-    }
-    p++;
   }
 #endif
   // Fall back to argv[0] if auxiliary vectors are not available.
@@ -239,7 +240,7 @@ std::string getMainExecutable(const char *argv0, void *MainAddr) {
   if (getprogpath(exe_path, argv0) != NULL)
     return exe_path;
 #elif defined(__linux__) || defined(__CYGWIN__) || defined(__gnu_hurd__)
-  char exe_path[MAXPATHLEN];
+  char exe_path[PATH_MAX];
   const char *aPath = "/proc/self/exe";
   if (sys::fs::exists(aPath)) {
     // /proc is not always mounted under Linux (chroot for example).
@@ -263,7 +264,7 @@ std::string getMainExecutable(const char *argv0, void *MainAddr) {
       return ret;
     }
 #else
-    char real_path[MAXPATHLEN];
+    char real_path[PATH_MAX];
     if (realpath(exe_path, real_path))
       return std::string(real_path);
 #endif
@@ -271,6 +272,26 @@ std::string getMainExecutable(const char *argv0, void *MainAddr) {
   // Fall back to the classical detection.
   if (getprogpath(exe_path, argv0))
     return exe_path;
+#elif defined(__MVS__)
+  int token = 0;
+  W_PSPROC buf;
+  char exe_path[PS_PATHBLEN];
+  pid_t pid = getpid();
+
+  memset(&buf, 0, sizeof(buf));
+  buf.ps_pathptr = exe_path;
+  buf.ps_pathlen = sizeof(exe_path);
+
+  while (true) {
+    if ((token = w_getpsent(token, &buf, sizeof(buf))) <= 0)
+      break;
+    if (buf.ps_pid != pid)
+      continue;
+    char real_path[PATH_MAX];
+    if (realpath(exe_path, real_path))
+      return std::string(real_path);
+    break;  // Found entry, but realpath failed.
+  }
 #elif defined(HAVE_DLFCN_H) && defined(HAVE_DLADDR)
   // Use dladdr to get executable path if available.
   Dl_info DLInfo;
@@ -280,7 +301,7 @@ std::string getMainExecutable(const char *argv0, void *MainAddr) {
 
   // If the filename is a symlink, we need to resolve and return the location of
   // the actual executable.
-  char link_path[MAXPATHLEN];
+  char link_path[PATH_MAX];
   if (realpath(DLInfo.dli_fname, link_path))
     return link_path;
 #else
@@ -330,12 +351,7 @@ std::error_code current_path(SmallVectorImpl<char> &result) {
     return std::error_code();
   }
 
-#ifdef MAXPATHLEN
-  result.reserve(MAXPATHLEN);
-#else
-// For GNU Hurd
-  result.reserve(1024);
-#endif
+  result.reserve(PATH_MAX);
 
   while (true) {
     if (::getcwd(result.data(), result.capacity()) == nullptr) {
@@ -504,6 +520,10 @@ static bool is_local_impl(struct STATVFS &Vfs) {
 
   // vmount entry not found; "remote" is the conservative answer.
   return false;
+#elif defined(__MVS__)
+  // The file system can have an arbitrary structure on z/OS; must go with the
+  // conservative answer.
+  return false;
 #else
   return !!(STATVFS_F_FLAG(Vfs) & MNT_LOCAL);
 #endif
@@ -998,7 +1018,7 @@ std::error_code openFileForRead(const Twine &Name, int &ResultFD,
 #if defined(F_GETPATH)
   // When F_GETPATH is availble, it is the quickest way to get
   // the real path name.
-  char Buffer[MAXPATHLEN];
+  char Buffer[PATH_MAX];
   if (::fcntl(ResultFD, F_GETPATH, Buffer) != -1)
     RealPath->append(Buffer, Buffer + strlen(Buffer));
 #else
@@ -1169,6 +1189,51 @@ static bool getDarwinConfDir(bool TempDir, SmallVectorImpl<char> &Result) {
   return false;
 }
 
+bool user_config_directory(SmallVectorImpl<char> &result) {
+#ifdef __APPLE__
+  // Mac: ~/Library/Preferences/
+  if (home_directory(result)) {
+    append(result, "Library", "Preferences");
+    return true;
+  }
+#else
+  // XDG_CONFIG_HOME as defined in the XDG Base Directory Specification:
+  // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
+  if (const char *RequestedDir = getenv("XDG_CONFIG_HOME")) {
+    result.clear();
+    result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
+    return true;
+  }
+#endif
+  // Fallback: ~/.config
+  if (!home_directory(result)) {
+    return false;
+  }
+  append(result, ".config");
+  return true;
+}
+
+bool cache_directory(SmallVectorImpl<char> &result) {
+#ifdef __APPLE__
+  if (getDarwinConfDir(false/*tempDir*/, result)) {
+    return true;
+  }
+#else
+  // XDG_CACHE_HOME as defined in the XDG Base Directory Specification:
+  // http://standards.freedesktop.org/basedir-spec/basedir-spec-latest.html
+  if (const char *RequestedDir = getenv("XDG_CACHE_HOME")) {
+    result.clear();
+    result.append(RequestedDir, RequestedDir + strlen(RequestedDir));
+    return true;
+  }
+#endif
+  if (!home_directory(result)) {
+    return false;
+  }
+  append(result, ".cache");
+  return true;
+}
+
 static const char *getEnvTempDir() {
   // Check whether the temporary directory is specified by an environment
   // variable.