unix,win: add uv_os_homedir()

PR-URL: https://github.com/libuv/libuv/pull/350
Reviewed-By: Ben Noordhuis <info@bnoordhuis.nl>
Reviewed-By: Saúl Ibarra Corretgé <saghul@gmail.com>

Makefile.am

@@ -45,7 +45,7 @@ include_HEADERS += include/uv-win.h include/tree.h
 AM_CPPFLAGS += -I$(top_srcdir)/src/win \
                -DWIN32_LEAN_AND_MEAN \
                -D_WIN32_WINNT=0x0600
-LIBS += -lws2_32 -lpsapi -liphlpapi -lshell32
+LIBS += -lws2_32 -lpsapi -liphlpapi -lole32 -lshell32
 libuv_la_SOURCES += src/win/async.c \
                     src/win/atomicops-inl.h \
                     src/win/core.c \
@@ -165,6 +165,7 @@ test_run_tests_SOURCES = test/blackhole-server.c \
                          test/test-getnameinfo.c \
                          test/test-getsockname.c \
                          test/test-handle-fileno.c \
+                         test/test-homedir.c \
                          test/test-hrtime.c \
                          test/test-idle.c \
                          test/test-ip4-addr.c \

checksparse.sh

@@ -103,6 +103,7 @@ test/test-get-loadavg.c
 test/test-get-memory.c
 test/test-getaddrinfo.c
 test/test-getsockname.c
+test/test-homedir.c
 test/test-hrtime.c
 test/test-idle.c
 test/test-ip6-addr.c

docs/src/misc.rst

@@ -227,6 +227,23 @@ API
 
     Changes the current working directory.
 
+.. c:function:: int uv_os_homedir(char* buffer, size_t* size)
+
+    Gets the current user's home directory. On Windows, `uv_os_homedir()` first
+    checks the `USERPROFILE` environment variable using
+    `GetEnvironmentVariableW()`. If `USERPROFILE` is not set,
+    `SHGetKnownFolderPath()` is called. On all other operating systems,
+    `uv_os_homedir()` first checks the `HOME` environment variable using
+    :man:`getenv(3)`. If `HOME` is not set, :man:`getpwuid_r(3)` is called. The
+    user's home directory is stored in `buffer`. When `uv_os_homedir()` is
+    called, `size` indicates the maximum size of `buffer`. On success or
+    `UV_ENOBUFS` failure, `size` is set to the string length of `buffer`.
+
+    .. warning::
+        `uv_os_homedir()` is not thread safe.
+
+    .. versionadded:: 1.6.0
+
 .. uint64_t uv_get_free_memory(void)
 .. c:function:: uint64_t uv_get_total_memory(void)
 

include/uv.h

@@ -1028,6 +1028,8 @@ typedef struct {
 
 UV_EXTERN int uv_getrusage(uv_rusage_t* rusage);
 
+UV_EXTERN int uv_os_homedir(char* buffer, size_t* size);
+
 UV_EXTERN int uv_cpu_info(uv_cpu_info_t** cpu_infos, int* count);
 UV_EXTERN void uv_free_cpu_info(uv_cpu_info_t* cpu_infos, int count);
 

src/unix/core.c

@@ -38,6 +38,7 @@
 #include <limits.h> /* INT_MAX, PATH_MAX */
 #include <sys/uio.h> /* writev */
 #include <sys/resource.h> /* getrusage */
+#include <pwd.h>
 
 #ifdef __linux__
 # include <sys/ioctl.h>
@@ -986,3 +987,82 @@ int uv__dup2_cloexec(int oldfd, int newfd) {
     return r;
   }
 }
+
+
+int uv_os_homedir(char* buffer, size_t* size) {
+  struct passwd pw;
+  struct passwd* result;
+  char* buf;
+  uid_t uid;
+  size_t bufsize;
+  size_t len;
+  int r;
+
+  if (buffer == NULL || size == NULL || *size == 0)
+    return -EINVAL;
+
+  /* Check if the HOME environment variable is set first */
+  buf = getenv("HOME");
+
+  if (buf != NULL) {
+    len = strlen(buf);
+
+    if (len >= *size) {
+      *size = len;
+      return -ENOBUFS;
+    }
+
+    memcpy(buffer, buf, len + 1);
+    *size = len;
+
+    return 0;
+  }
+
+  /* HOME is not set, so call getpwuid() */
+  bufsize = sysconf(_SC_GETPW_R_SIZE_MAX);
+
+  if (bufsize <= 0)
+    return -EIO;
+
+  uid = getuid();
+  buf = NULL;
+
+  for (;;) {
+    free(buf);
+    buf = malloc(bufsize);
+
+    if (buf == NULL)
+      return -ENOMEM;
+
+    r = getpwuid_r(uid, &pw, buf, bufsize, &result);
+
+    if (r != ERANGE)
+      break;
+
+    bufsize *= 2;
+  }
+
+  if (r != 0) {
+    free(buf);
+    return -r;
+  }
+
+  if (result == NULL) {
+    free(buf);
+    return -ENOENT;
+  }
+
+  len = strlen(pw.pw_dir);
+
+  if (len >= *size) {
+    *size = len;
+    free(buf);
+    return -ENOBUFS;
+  }
+
+  memcpy(buffer, pw.pw_dir, len + 1);
+  *size = len;
+  free(buf);
+
+  return 0;
+}

src/win/util.c

@@ -36,6 +36,8 @@
 #include <psapi.h>
 #include <tlhelp32.h>
 #include <windows.h>
+#include <shlobj.h>
+#include <objbase.h>
 
 
 /*
@@ -72,7 +74,7 @@ void uv__util_init() {
   InitializeCriticalSection(&process_title_lock);
 
   /* Retrieve high-resolution timer frequency
-   * and precompute its reciprocal. 
+   * and precompute its reciprocal.
    */
   if (QueryPerformanceFrequency(&perf_frequency)) {
     hrtime_interval_ = 1.0 / perf_frequency.QuadPart;
@@ -801,8 +803,8 @@ static int is_windows_version_or_greater(DWORD os_major,
 
   /* Perform the test. */
   return (int) VerifyVersionInfo(
-    &osvi, 
-    VER_MAJORVERSION | VER_MINORVERSION | 
+    &osvi,
+    VER_MAJORVERSION | VER_MINORVERSION |
     VER_SERVICEPACKMAJOR | VER_SERVICEPACKMINOR,
     condition_mask);
 }
@@ -870,7 +872,7 @@ int uv_interface_addresses(uv_interface_address_t** addresses_ptr,
     flags = GAA_FLAG_SKIP_ANYCAST | GAA_FLAG_SKIP_MULTICAST |
       GAA_FLAG_SKIP_DNS_SERVER | GAA_FLAG_INCLUDE_PREFIX;
   }
-  
+
 
   /* Fetch the size of the adapters reported by windows, and then get the */
   /* list itself. */
@@ -1053,14 +1055,14 @@ int uv_interface_addresses(uv_interface_address_t** addresses_ptr,
               prefix->PrefixLength <= prefix_len)
             continue;
 
-          if (address_prefix_match(sa->sa_family, sa, 
+          if (address_prefix_match(sa->sa_family, sa,
               prefix->Address.lpSockaddr, prefix->PrefixLength)) {
             prefix_len = prefix->PrefixLength;
           }
         }
 
         /* If there is no matching prefix information, return a single-host
-         * subnet mask (e.g. 255.255.255.255 for IPv4). 
+         * subnet mask (e.g. 255.255.255.255 for IPv4).
          */
         if (!prefix_len)
           prefix_len = (sa->sa_family == AF_INET6) ? 128 : 32;
@@ -1153,3 +1155,67 @@ int uv_getrusage(uv_rusage_t *uv_rusage) {
 
   return 0;
 }
+
+
+int uv_os_homedir(char* buffer, size_t* size) {
+  wchar_t* path;
+  size_t bufsize;
+  size_t len;
+  int r;
+
+  if (buffer == NULL || size == NULL || *size == 0)
+    return UV_EINVAL;
+
+  /* Check if the USERPROFILE environment variable is set first */
+  path = malloc(*size * sizeof(WCHAR));
+
+  if (path == NULL)
+    return UV_ENOMEM;
+
+  len = GetEnvironmentVariableW(L"USERPROFILE", path, *size);
+
+  if (len == 0) {
+    r = GetLastError();
+    free(path);
+
+    if (r != ERROR_ENVVAR_NOT_FOUND)
+      return uv_translate_sys_error(r);
+  } else {
+    if (len > *size) {
+      free(path);
+      *size = len - 1;
+      return UV_ENOBUFS;
+    }
+
+    bufsize = uv_utf16_to_utf8(path, -1, buffer, *size);
+    assert(len + 1 == bufsize);
+    free(path);
+    *size = len;
+
+    return 0;
+  }
+
+  /* USERPROFILE is not set, so call SHGetKnownFolderPath() */
+  if (SHGetKnownFolderPath(&FOLDERID_Profile, 0, NULL, &path) != S_OK)
+    return uv_translate_sys_error(GetLastError());
+
+  bufsize = uv_utf16_to_utf8(path, -1, buffer, *size);
+
+  if (bufsize == 0) {
+    r = GetLastError();
+
+    if (r == ERROR_INSUFFICIENT_BUFFER) {
+      *size = wcslen(path);
+      CoTaskMemFree(path);
+      return UV_ENOBUFS;
+    }
+
+    CoTaskMemFree(path);
+    return uv_translate_sys_error(r);
+  }
+
+  CoTaskMemFree(path);
+  *size = bufsize - 1;
+
+  return 0;
+}

test/test-homedir.c

@@ -0,0 +1,49 @@
+#include "uv.h"
+#include "task.h"
+#include <string.h>
+
+#define PATHMAX 1024
+#define SMALLPATH 1
+
+TEST_IMPL(homedir) {
+  char homedir[PATHMAX];
+  size_t len;
+  char last;
+  int r;
+
+  /* Test the normal case */
+  len = sizeof homedir;
+  homedir[0] = '\0';
+  ASSERT(strlen(homedir) == 0);
+  r = uv_os_homedir(homedir, &len);
+  ASSERT(r == 0);
+  ASSERT(strlen(homedir) == len);
+  ASSERT(len > 0);
+  ASSERT(homedir[len] == '\0');
+
+  if (len > 1) {
+    last = homedir[len - 1];
+#ifdef _WIN32
+    ASSERT(last != '\\');
+#else
+    ASSERT(last != '/');
+#endif
+  }
+
+  /* Test the case where the buffer is too small */
+  len = SMALLPATH;
+  r = uv_os_homedir(homedir, &len);
+  ASSERT(r == UV_ENOBUFS);
+  ASSERT(len > SMALLPATH);
+
+  /* Test invalid inputs */
+  r = uv_os_homedir(NULL, &len);
+  ASSERT(r == UV_EINVAL);
+  r = uv_os_homedir(homedir, NULL);
+  ASSERT(r == UV_EINVAL);
+  len = 0;
+  r = uv_os_homedir(homedir, &len);
+  ASSERT(r == UV_EINVAL);
+
+  return 0;
+}

test/test-list.h

@@ -183,6 +183,7 @@ TEST_DECLARE   (process_title)
 TEST_DECLARE   (cwd_and_chdir)
 TEST_DECLARE   (get_memory)
 TEST_DECLARE   (handle_fileno)
+TEST_DECLARE   (homedir)
 TEST_DECLARE   (hrtime)
 TEST_DECLARE   (getaddrinfo_fail)
 TEST_DECLARE   (getaddrinfo_fail_sync)
@@ -542,6 +543,8 @@ TASK_LIST_START
 
   TEST_ENTRY  (handle_fileno)
 
+  TEST_ENTRY  (homedir)
+
   TEST_ENTRY  (hrtime)
 
   TEST_ENTRY_CUSTOM (getaddrinfo_fail, 0, 0, 10000)

uv.gyp

@@ -108,6 +108,7 @@
             'libraries': [
               '-ladvapi32',
               '-liphlpapi',
+              '-lole32',
               '-lpsapi',
               '-lshell32',
               '-lws2_32'
@@ -304,6 +305,7 @@
         'test/test-getnameinfo.c',
         'test/test-getsockname.c',
         'test/test-handle-fileno.c',
+        'test/test-homedir.c',
         'test/test-hrtime.c',
         'test/test-idle.c',
         'test/test-ip6-addr.c',