unix,win: add gecos field to uv_passwd_t

On Unix the gecos field usually contains the full name
of the user. This is returned by getpwuid_r() on Unix
and GetUserNameExW on Windows (falling back to
NameSamCompatible if the users display name is not set).

Co-authored-by: cjihrig <cjihrig@gmail.com>
Co-authored-by: Saúl Ibarra Corretgé <saghul@gmail.com>
Refs: https://github.com/libuv/libuv/pull/834
Fixes: https://github.com/libuv/libuv/issues/831
PR-URL: https://github.com/libuv/libuv/pull/1789
Reviewed-By: Santiago Gimeno <santiago.gimeno@gmail.com>

configure.ac

@@ -64,7 +64,7 @@ AM_CONDITIONAL([OS390],    [AS_CASE([$host_os],[openedition*],  [true], [false])
 AM_CONDITIONAL([SUNOS],    [AS_CASE([$host_os],[solaris*],      [true], [false])])
 AM_CONDITIONAL([WINNT],    [AS_CASE([$host_os],[mingw*],        [true], [false])])
 AS_CASE([$host_os],[mingw*], [
-    LIBS="$LIBS -lws2_32 -lpsapi -liphlpapi -lshell32 -luserenv -luser32"
+    LIBS="$LIBS -lws2_32 -lpsapi -liphlpapi -lshell32 -lsecur32 -luserenv -luser32"
 ])
 AS_CASE([$host_os], [netbsd*], [AC_CHECK_LIB([kvm], [kvm_open])])
 AC_CHECK_HEADERS([sys/ahafs_evProds.h])

docs/src/misc.rst

@@ -140,6 +140,7 @@ Data types
             long gid;
             char* shell;
             char* homedir;
+            char* gecos;
         } uv_passwd_t;
 
 
@@ -422,6 +423,8 @@ API
 
     .. versionadded:: 1.9.0
 
+    .. versionchanged:: 2.0.0 `gecos` support is added.
+
 .. c:function:: void uv_os_free_passwd(uv_passwd_t* pwd)
 
     Frees the `pwd` memory previously allocated with :c:func:`uv_os_get_passwd`.

include/uv.h

@@ -1096,6 +1096,7 @@ struct uv_passwd_s {
   long gid;
   char* shell;
   char* homedir;
+  char* gecos;
 };
 
 typedef enum {

src/unix/core.c

@@ -1155,6 +1155,7 @@ int uv__getpwuid_r(uv_passwd_t* pwd) {
   size_t name_size;
   size_t homedir_size;
   size_t shell_size;
+  size_t gecos_size;
   long initsize;
   int r;
 #if defined(__ANDROID_API__) && __ANDROID_API__ < 21
@@ -1203,11 +1204,24 @@ int uv__getpwuid_r(uv_passwd_t* pwd) {
     return UV_ENOENT;
   }
 
-  /* Allocate memory for the username, shell, and home directory */
+  /* Allocate memory for the username, gecos, shell, and home directory. */
   name_size = strlen(pw.pw_name) + 1;
   homedir_size = strlen(pw.pw_dir) + 1;
   shell_size = strlen(pw.pw_shell) + 1;
-  pwd->username = uv__malloc(name_size + homedir_size + shell_size);
+
+#ifdef __MVS__
+  gecos_size = 0; /* pw_gecos does not exist on zOS. */
+#else
+  if (pw.pw_gecos != NULL)
+    gecos_size = strlen(pw.pw_gecos) + 1;
+  else
+    gecos_size = 0;
+#endif
+
+  pwd->username = uv__malloc(name_size +
+                             homedir_size +
+                             shell_size +
+                             gecos_size);
 
   if (pwd->username == NULL) {
     uv__free(buf);
@@ -1225,6 +1239,18 @@ int uv__getpwuid_r(uv_passwd_t* pwd) {
   pwd->shell = pwd->homedir + homedir_size;
   memcpy(pwd->shell, pw.pw_shell, shell_size);
 
+  /* Copy the gecos field */
+#ifdef __MVS__
+  pwd->gecos = NULL;  /* pw_gecos does not exist on zOS. */
+#else
+  if (pw.pw_gecos == NULL) {
+    pwd->gecos = NULL;
+  } else {
+    pwd->gecos = pwd->shell + shell_size;
+    memcpy(pwd->gecos, pw.pw_gecos, gecos_size);
+  }
+#endif
+
   /* Copy the uid and gid */
   pwd->uid = pw.pw_uid;
   pwd->gid = pw.pw_gid;
@@ -1240,7 +1266,7 @@ void uv_os_free_passwd(uv_passwd_t* pwd) {
     return;
 
   /*
-    The memory for name, shell, and homedir are allocated in a single
+    The memory for name, shell, homedir, and gecos are allocated in a single
     uv__malloc() call. The base of the pointer is stored in pwd->username, so
     that is the field that needs to be freed.
   */
@@ -1248,6 +1274,7 @@ void uv_os_free_passwd(uv_passwd_t* pwd) {
   pwd->username = NULL;
   pwd->shell = NULL;
   pwd->homedir = NULL;
+  pwd->gecos = NULL;
 }
 
 

src/win/util.c

@@ -35,6 +35,9 @@
 #include <windows.h>
 #include <userenv.h>
 
+#define SECURITY_WIN32
+#include <security.h>
+
 
 /*
  * Max title length; the only thing MSDN tells us about the maximum length
@@ -1169,8 +1172,10 @@ void uv_os_free_passwd(uv_passwd_t* pwd) {
 
   uv__free(pwd->username);
   uv__free(pwd->homedir);
+  uv__free(pwd->gecos);
   pwd->username = NULL;
   pwd->homedir = NULL;
+  pwd->gecos = NULL;
 }
 
 
@@ -1275,6 +1280,9 @@ int uv__getpwuid_r(uv_passwd_t* pwd) {
   wchar_t username[UNLEN + 1];
   wchar_t path[MAX_PATH];
   DWORD bufsize;
+  wchar_t* gecosbuf;
+  ULONG gecos_size;
+  EXTENDED_NAME_FORMAT name_format;
   int r;
 
   if (pwd == NULL)
@@ -1310,18 +1318,60 @@ int uv__getpwuid_r(uv_passwd_t* pwd) {
     return uv_translate_sys_error(r);
   }
 
+  /* Set all of the pointers to NULL in case an error is encountered. */
   pwd->homedir = NULL;
+  pwd->username = NULL;
+  pwd->gecos = NULL;
+  gecosbuf = NULL;
+
+  /* Get the gecos using GetUserNameExW() */
+  gecos_size = 0;
+  /* Try using the display name first. */
+  GetUserNameExW(NameDisplay, NULL, &gecos_size);
+  if (GetLastError() == ERROR_MORE_DATA) {
+    name_format = NameDisplay;
+  } else {
+    /* NameDisplay not available, so try NameSamCompatible. */
+    GetUserNameExW(NameSamCompatible, NULL, &gecos_size);
+    if (GetLastError() == ERROR_MORE_DATA) {
+      name_format = NameSamCompatible;
+    } else {
+      /* Unsupported */
+      gecos_size = 0;
+    }
+  }
+
+  if (gecos_size > 0) {
+    gecosbuf = uv__malloc(sizeof(wchar_t) * gecos_size);
+    if (gecosbuf == NULL) {
+      r = UV_ENOMEM;
+      goto error;
+    }
+
+    if (GetUserNameExW(name_format, gecosbuf, &gecos_size) == 0) {
+      r = uv_translate_sys_error(GetLastError());
+      goto error;
+    }
+  }
+
+  /* Populate the uv_passwd_t structure. */
   r = uv__convert_utf16_to_utf8(path, -1, &pwd->homedir);
 
   if (r != 0)
-    return r;
+    goto error;
 
-  pwd->username = NULL;
   r = uv__convert_utf16_to_utf8(username, -1, &pwd->username);
 
-  if (r != 0) {
-    uv__free(pwd->homedir);
-    return r;
+  if (r != 0)
+    goto error;
+
+  if (gecosbuf != NULL) {
+    r = uv__convert_utf16_to_utf8(gecosbuf, -1, &pwd->gecos);
+
+    if (r != 0)
+      goto error;
+
+    uv__free(gecosbuf);
   }
 
   pwd->shell = NULL;
@@ -1329,6 +1379,13 @@ int uv__getpwuid_r(uv_passwd_t* pwd) {
   pwd->gid = -1;
 
   return 0;
+
+error:
+  uv__free(gecosbuf);
+  uv__free(pwd->homedir);
+  uv__free(pwd->username);
+  uv__free(pwd->gecos);
+  return r;
 }
 
 

test/test-get-passwd.c

@@ -70,6 +70,7 @@ TEST_IMPL(get_passwd) {
   ASSERT(pwd.username == NULL);
   ASSERT(pwd.shell == NULL);
   ASSERT(pwd.homedir == NULL);
+  ASSERT(pwd.gecos == NULL);
 
   /* Test a double free */
   uv_os_free_passwd(&pwd);
@@ -77,6 +78,7 @@ TEST_IMPL(get_passwd) {
   ASSERT(pwd.username == NULL);
   ASSERT(pwd.shell == NULL);
   ASSERT(pwd.homedir == NULL);
+  ASSERT(pwd.gecos == NULL);
 
   /* Test invalid input */
   r = uv_os_get_passwd(NULL);

test/test-platform-output.c

@@ -145,6 +145,7 @@ TEST_IMPL(platform_output) {
   printf("  username: %s\n", pwd.username);
   printf("  shell: %s\n", pwd.shell);
   printf("  home directory: %s\n", pwd.homedir);
+  printf("  gecos: %s\n", pwd.gecos);
 
   pid = uv_os_getpid();
   ASSERT(pid > 0);

uv.gyp

@@ -135,6 +135,7 @@
               '-liphlpapi',
               '-lpsapi',
               '-lshell32',
+              '-lsecur32',
               '-luser32',
               '-luserenv',
               '-lws2_32'