Code

Merge branch 'maint'
[git.git] / compat / mingw.c
index 6b5b5b2c7011a89c0415ebb89406c4a3ac53e9a9..bee605441910caeddd1e94eb7795f615a3d1348a 100644 (file)
@@ -3,9 +3,7 @@
 #include <conio.h>
 #include "../strbuf.h"
 
-#include <shellapi.h>
-
-static int err_win_to_posix(DWORD winerr)
+int err_win_to_posix(DWORD winerr)
 {
        int error = ENOSYS;
        switch(winerr) {
@@ -129,7 +127,7 @@ int mingw_open (const char *filename, int oflags, ...)
        mode = va_arg(args, int);
        va_end(args);
 
-       if (!strcmp(filename, "/dev/null"))
+       if (filename && !strcmp(filename, "/dev/null"))
                filename = "nul";
 
        fd = open(filename, oflags, mode);
@@ -142,23 +140,68 @@ int mingw_open (const char *filename, int oflags, ...)
        return fd;
 }
 
-static inline time_t filetime_to_time_t(const FILETIME *ft)
+#undef write
+ssize_t mingw_write(int fd, const void *buf, size_t count)
+{
+       /*
+        * While write() calls to a file on a local disk are translated
+        * into WriteFile() calls with a maximum size of 64KB on Windows
+        * XP and 256KB on Vista, no such cap is placed on writes to
+        * files over the network on Windows XP.  Unfortunately, there
+        * seems to be a limit of 32MB-28KB on X64 and 64MB-32KB on x86;
+        * bigger writes fail on Windows XP.
+        * So we cap to a nice 31MB here to avoid write failures over
+        * the net without changing the number of WriteFile() calls in
+        * the local case.
+        */
+       return write(fd, buf, min(count, 31 * 1024 * 1024));
+}
+
+#undef fopen
+FILE *mingw_fopen (const char *filename, const char *otype)
+{
+       if (filename && !strcmp(filename, "/dev/null"))
+               filename = "nul";
+       return fopen(filename, otype);
+}
+
+#undef freopen
+FILE *mingw_freopen (const char *filename, const char *otype, FILE *stream)
+{
+       if (filename && !strcmp(filename, "/dev/null"))
+               filename = "nul";
+       return freopen(filename, otype, stream);
+}
+
+/*
+ * The unit of FILETIME is 100-nanoseconds since January 1, 1601, UTC.
+ * Returns the 100-nanoseconds ("hekto nanoseconds") since the epoch.
+ */
+static inline long long filetime_to_hnsec(const FILETIME *ft)
 {
        long long winTime = ((long long)ft->dwHighDateTime << 32) + ft->dwLowDateTime;
-       winTime -= 116444736000000000LL; /* Windows to Unix Epoch conversion */
-       winTime /= 10000000;             /* Nano to seconds resolution */
-       return (time_t)winTime;
+       /* Windows to Unix Epoch conversion */
+       return winTime - 116444736000000000LL;
+}
+
+static inline time_t filetime_to_time_t(const FILETIME *ft)
+{
+       return (time_t)(filetime_to_hnsec(ft) / 10000000);
 }
 
 /* We keep the do_lstat code in a separate function to avoid recursion.
  * When a path ends with a slash, the stat will fail with ENOENT. In
  * this case, we strip the trailing slashes and stat again.
+ *
+ * If follow is true then act like stat() and report on the link
+ * target. Otherwise report on the link itself.
  */
-static int do_lstat(const char *file_name, struct stat *buf)
+static int do_lstat(int follow, const char *file_name, struct stat *buf)
 {
+       int err;
        WIN32_FILE_ATTRIBUTE_DATA fdata;
 
-       if (!(errno = get_file_attr(file_name, &fdata))) {
+       if (!(err = get_file_attr(file_name, &fdata))) {
                buf->st_ino = 0;
                buf->st_gid = 0;
                buf->st_uid = 0;
@@ -170,8 +213,28 @@ static int do_lstat(const char *file_name, struct stat *buf)
                buf->st_atime = filetime_to_time_t(&(fdata.ftLastAccessTime));
                buf->st_mtime = filetime_to_time_t(&(fdata.ftLastWriteTime));
                buf->st_ctime = filetime_to_time_t(&(fdata.ftCreationTime));
+               if (fdata.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) {
+                       WIN32_FIND_DATAA findbuf;
+                       HANDLE handle = FindFirstFileA(file_name, &findbuf);
+                       if (handle != INVALID_HANDLE_VALUE) {
+                               if ((findbuf.dwFileAttributes & FILE_ATTRIBUTE_REPARSE_POINT) &&
+                                               (findbuf.dwReserved0 == IO_REPARSE_TAG_SYMLINK)) {
+                                       if (follow) {
+                                               char buffer[MAXIMUM_REPARSE_DATA_BUFFER_SIZE];
+                                               buf->st_size = readlink(file_name, buffer, MAXIMUM_REPARSE_DATA_BUFFER_SIZE);
+                                       } else {
+                                               buf->st_mode = S_IFLNK;
+                                       }
+                                       buf->st_mode |= S_IREAD;
+                                       if (!(findbuf.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
+                                               buf->st_mode |= S_IWRITE;
+                               }
+                               FindClose(handle);
+                       }
+               }
                return 0;
        }
+       errno = err;
        return -1;
 }
 
@@ -181,12 +244,12 @@ static int do_lstat(const char *file_name, struct stat *buf)
  * complete. Note that Git stat()s are redirected to mingw_lstat()
  * too, since Windows doesn't really handle symlinks that well.
  */
-int mingw_lstat(const char *file_name, struct stat *buf)
+static int do_stat_internal(int follow, const char *file_name, struct stat *buf)
 {
        int namelen;
        static char alt_name[PATH_MAX];
 
-       if (!do_lstat(file_name, buf))
+       if (!do_lstat(follow, file_name, buf))
                return 0;
 
        /* if file_name ended in a '/', Windows returned ENOENT;
@@ -205,7 +268,16 @@ int mingw_lstat(const char *file_name, struct stat *buf)
 
        memcpy(alt_name, file_name, namelen);
        alt_name[namelen] = 0;
-       return do_lstat(alt_name, buf);
+       return do_lstat(follow, alt_name, buf);
+}
+
+int mingw_lstat(const char *file_name, struct stat *buf)
+{
+       return do_stat_internal(0, file_name, buf);
+}
+int mingw_stat(const char *file_name, struct stat *buf)
+{
+       return do_stat_internal(1, file_name, buf);
 }
 
 #undef fstat
@@ -253,17 +325,38 @@ int mingw_utime (const char *file_name, const struct utimbuf *times)
        int fh, rc;
 
        /* must have write permission */
-       if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0)
-               return -1;
+       DWORD attrs = GetFileAttributes(file_name);
+       if (attrs != INVALID_FILE_ATTRIBUTES &&
+           (attrs & FILE_ATTRIBUTE_READONLY)) {
+               /* ignore errors here; open() will report them */
+               SetFileAttributes(file_name, attrs & ~FILE_ATTRIBUTE_READONLY);
+       }
 
-       time_t_to_filetime(times->modtime, &mft);
-       time_t_to_filetime(times->actime, &aft);
+       if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0) {
+               rc = -1;
+               goto revert_attrs;
+       }
+
+       if (times) {
+               time_t_to_filetime(times->modtime, &mft);
+               time_t_to_filetime(times->actime, &aft);
+       } else {
+               GetSystemTimeAsFileTime(&mft);
+               aft = mft;
+       }
        if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
                errno = EINVAL;
                rc = -1;
        } else
                rc = 0;
        close(fh);
+
+revert_attrs:
+       if (attrs != INVALID_FILE_ATTRIBUTES &&
+           (attrs & FILE_ATTRIBUTE_READONLY)) {
+               /* ignore errors again */
+               SetFileAttributes(file_name, attrs);
+       }
        return rc;
 }
 
@@ -283,129 +376,37 @@ int mkstemp(char *template)
 
 int gettimeofday(struct timeval *tv, void *tz)
 {
-       SYSTEMTIME st;
-       struct tm tm;
-       GetSystemTime(&st);
-       tm.tm_year = st.wYear-1900;
-       tm.tm_mon = st.wMonth-1;
-       tm.tm_mday = st.wDay;
-       tm.tm_hour = st.wHour;
-       tm.tm_min = st.wMinute;
-       tm.tm_sec = st.wSecond;
-       tv->tv_sec = tm_to_time_t(&tm);
-       if (tv->tv_sec < 0)
-               return -1;
-       tv->tv_usec = st.wMilliseconds*1000;
+       FILETIME ft;
+       long long hnsec;
+
+       GetSystemTimeAsFileTime(&ft);
+       hnsec = filetime_to_hnsec(&ft);
+       tv->tv_sec = hnsec / 10000000;
+       tv->tv_usec = (hnsec % 10000000) / 10;
        return 0;
 }
 
 int pipe(int filedes[2])
 {
-       int fd;
-       HANDLE h[2], parent;
+       HANDLE h[2];
 
-       if (_pipe(filedes, 8192, 0) < 0)
-               return -1;
-
-       parent = GetCurrentProcess();
-
-       if (!DuplicateHandle (parent, (HANDLE)_get_osfhandle(filedes[0]),
-                       parent, &h[0], 0, FALSE, DUPLICATE_SAME_ACCESS)) {
-               close(filedes[0]);
-               close(filedes[1]);
-               return -1;
-       }
-       if (!DuplicateHandle (parent, (HANDLE)_get_osfhandle(filedes[1]),
-                       parent, &h[1], 0, FALSE, DUPLICATE_SAME_ACCESS)) {
-               close(filedes[0]);
-               close(filedes[1]);
-               CloseHandle(h[0]);
+       /* this creates non-inheritable handles */
+       if (!CreatePipe(&h[0], &h[1], NULL, 8192)) {
+               errno = err_win_to_posix(GetLastError());
                return -1;
        }
-       fd = _open_osfhandle((int)h[0], O_NOINHERIT);
-       if (fd < 0) {
-               close(filedes[0]);
-               close(filedes[1]);
+       filedes[0] = _open_osfhandle((int)h[0], O_NOINHERIT);
+       if (filedes[0] < 0) {
                CloseHandle(h[0]);
                CloseHandle(h[1]);
                return -1;
        }
-       close(filedes[0]);
-       filedes[0] = fd;
-       fd = _open_osfhandle((int)h[1], O_NOINHERIT);
-       if (fd < 0) {
+       filedes[1] = _open_osfhandle((int)h[1], O_NOINHERIT);
+       if (filedes[0] < 0) {
                close(filedes[0]);
-               close(filedes[1]);
                CloseHandle(h[1]);
                return -1;
        }
-       close(filedes[1]);
-       filedes[1] = fd;
-       return 0;
-}
-
-int poll(struct pollfd *ufds, unsigned int nfds, int timeout)
-{
-       int i, pending;
-
-       if (timeout >= 0) {
-               if (nfds == 0) {
-                       Sleep(timeout);
-                       return 0;
-               }
-               return errno = EINVAL, error("poll timeout not supported");
-       }
-
-       /* When there is only one fd to wait for, then we pretend that
-        * input is available and let the actual wait happen when the
-        * caller invokes read().
-        */
-       if (nfds == 1) {
-               if (!(ufds[0].events & POLLIN))
-                       return errno = EINVAL, error("POLLIN not set");
-               ufds[0].revents = POLLIN;
-               return 0;
-       }
-
-repeat:
-       pending = 0;
-       for (i = 0; i < nfds; i++) {
-               DWORD avail = 0;
-               HANDLE h = (HANDLE) _get_osfhandle(ufds[i].fd);
-               if (h == INVALID_HANDLE_VALUE)
-                       return -1;      /* errno was set */
-
-               if (!(ufds[i].events & POLLIN))
-                       return errno = EINVAL, error("POLLIN not set");
-
-               /* this emulation works only for pipes */
-               if (!PeekNamedPipe(h, NULL, 0, NULL, &avail, NULL)) {
-                       int err = GetLastError();
-                       if (err == ERROR_BROKEN_PIPE) {
-                               ufds[i].revents = POLLHUP;
-                               pending++;
-                       } else {
-                               errno = EINVAL;
-                               return error("PeekNamedPipe failed,"
-                                       " GetLastError: %u", err);
-                       }
-               } else if (avail) {
-                       ufds[i].revents = POLLIN;
-                       pending++;
-               } else
-                       ufds[i].revents = 0;
-       }
-       if (!pending) {
-               /* The only times that we spin here is when the process
-                * that is connected through the pipes is waiting for
-                * its own input data to become available. But since
-                * the process (pack-objects) is itself CPU intensive,
-                * it will happily pick up the time slice that we are
-                * relinquishing here.
-                */
-               Sleep(0);
-               goto repeat;
-       }
        return 0;
 }
 
@@ -613,7 +614,7 @@ static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_on
 }
 
 /*
- * Determines the absolute path of cmd using the the split path in path.
+ * Determines the absolute path of cmd using the split path in path.
  * If cmd contains a slash or backslash, no lookup is performed.
  */
 static char *path_lookup(const char *cmd, char **path, int exe_only)
@@ -638,8 +639,17 @@ static int env_compare(const void *a, const void *b)
        return strcasecmp(*ea, *eb);
 }
 
-static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
-                          int prepend_cmd)
+struct pinfo_t {
+       struct pinfo_t *next;
+       pid_t pid;
+       HANDLE proc;
+} pinfo_t;
+struct pinfo_t *pinfo = NULL;
+CRITICAL_SECTION pinfo_cs;
+
+static pid_t mingw_spawnve_fd(const char *cmd, const char **argv, char **env,
+                             const char *dir,
+                             int prepend_cmd, int fhin, int fhout, int fherr)
 {
        STARTUPINFO si;
        PROCESS_INFORMATION pi;
@@ -675,9 +685,9 @@ static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
        memset(&si, 0, sizeof(si));
        si.cb = sizeof(si);
        si.dwFlags = STARTF_USESTDHANDLES;
-       si.hStdInput = (HANDLE) _get_osfhandle(0);
-       si.hStdOutput = (HANDLE) _get_osfhandle(1);
-       si.hStdError = (HANDLE) _get_osfhandle(2);
+       si.hStdInput = (HANDLE) _get_osfhandle(fhin);
+       si.hStdOutput = (HANDLE) _get_osfhandle(fhout);
+       si.hStdError = (HANDLE) _get_osfhandle(fherr);
 
        /* concatenate argv, quoting args as we go */
        strbuf_init(&args, 0);
@@ -718,7 +728,7 @@ static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
 
        memset(&pi, 0, sizeof(pi));
        ret = CreateProcess(cmd, args.buf, NULL, NULL, TRUE, flags,
-               env ? envblk.buf : NULL, NULL, &si, &pi);
+               env ? envblk.buf : NULL, dir, &si, &pi);
 
        if (env)
                strbuf_release(&envblk);
@@ -729,10 +739,37 @@ static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
                return -1;
        }
        CloseHandle(pi.hThread);
-       return (pid_t)pi.hProcess;
+
+       /*
+        * The process ID is the human-readable identifier of the process
+        * that we want to present in log and error messages. The handle
+        * is not useful for this purpose. But we cannot close it, either,
+        * because it is not possible to turn a process ID into a process
+        * handle after the process terminated.
+        * Keep the handle in a list for waitpid.
+        */
+       EnterCriticalSection(&pinfo_cs);
+       {
+               struct pinfo_t *info = xmalloc(sizeof(struct pinfo_t));
+               info->pid = pi.dwProcessId;
+               info->proc = pi.hProcess;
+               info->next = pinfo;
+               pinfo = info;
+       }
+       LeaveCriticalSection(&pinfo_cs);
+
+       return (pid_t)pi.dwProcessId;
 }
 
-pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env)
+static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
+                          int prepend_cmd)
+{
+       return mingw_spawnve_fd(cmd, argv, env, NULL, prepend_cmd, 0, 1, 2);
+}
+
+pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env,
+                    const char *dir,
+                    int fhin, int fhout, int fherr)
 {
        pid_t pid;
        char **path = get_path_split();
@@ -754,13 +791,15 @@ pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env)
                                pid = -1;
                        }
                        else {
-                               pid = mingw_spawnve(iprog, argv, env, 1);
+                               pid = mingw_spawnve_fd(iprog, argv, env, dir, 1,
+                                                      fhin, fhout, fherr);
                                free(iprog);
                        }
                        argv[0] = argv0;
                }
                else
-                       pid = mingw_spawnve(prog, argv, env, 0);
+                       pid = mingw_spawnve_fd(prog, argv, env, dir, 0,
+                                              fhin, fhout, fherr);
                free(prog);
        }
        free_path_split(path);
@@ -829,6 +868,30 @@ void mingw_execvp(const char *cmd, char *const *argv)
        free_path_split(path);
 }
 
+void mingw_execv(const char *cmd, char *const *argv)
+{
+       mingw_execve(cmd, argv, environ);
+}
+
+int mingw_kill(pid_t pid, int sig)
+{
+       if (pid > 0 && sig == SIGTERM) {
+               HANDLE h = OpenProcess(PROCESS_TERMINATE, FALSE, pid);
+
+               if (TerminateProcess(h, -1)) {
+                       CloseHandle(h);
+                       return 0;
+               }
+
+               errno = err_win_to_posix(GetLastError());
+               CloseHandle(h);
+               return -1;
+       }
+
+       errno = EINVAL;
+       return -1;
+}
+
 static char **copy_environ(void)
 {
        char **env;
@@ -903,23 +966,216 @@ char **make_augmented_environ(const char *const *vars)
        return env;
 }
 
-/* this is the first function to call into WS_32; initialize it */
-#undef gethostbyname
-struct hostent *mingw_gethostbyname(const char *host)
+/*
+ * Note, this isn't a complete replacement for getaddrinfo. It assumes
+ * that service contains a numerical port, or that it it is null. It
+ * does a simple search using gethostbyname, and returns one IPv4 host
+ * if one was found.
+ */
+static int WSAAPI getaddrinfo_stub(const char *node, const char *service,
+                                  const struct addrinfo *hints,
+                                  struct addrinfo **res)
+{
+       struct hostent *h = NULL;
+       struct addrinfo *ai;
+       struct sockaddr_in *sin;
+
+       if (node) {
+               h = gethostbyname(node);
+               if (!h)
+                       return WSAGetLastError();
+       }
+
+       ai = xmalloc(sizeof(struct addrinfo));
+       *res = ai;
+       ai->ai_flags = 0;
+       ai->ai_family = AF_INET;
+       ai->ai_socktype = hints ? hints->ai_socktype : 0;
+       switch (ai->ai_socktype) {
+       case SOCK_STREAM:
+               ai->ai_protocol = IPPROTO_TCP;
+               break;
+       case SOCK_DGRAM:
+               ai->ai_protocol = IPPROTO_UDP;
+               break;
+       default:
+               ai->ai_protocol = 0;
+               break;
+       }
+       ai->ai_addrlen = sizeof(struct sockaddr_in);
+       if (hints && (hints->ai_flags & AI_CANONNAME))
+               ai->ai_canonname = h ? strdup(h->h_name) : NULL;
+       else
+               ai->ai_canonname = NULL;
+
+       sin = xmalloc(ai->ai_addrlen);
+       memset(sin, 0, ai->ai_addrlen);
+       sin->sin_family = AF_INET;
+       /* Note: getaddrinfo is supposed to allow service to be a string,
+        * which should be looked up using getservbyname. This is
+        * currently not implemented */
+       if (service)
+               sin->sin_port = htons(atoi(service));
+       if (h)
+               sin->sin_addr = *(struct in_addr *)h->h_addr;
+       else if (hints && (hints->ai_flags & AI_PASSIVE))
+               sin->sin_addr.s_addr = INADDR_ANY;
+       else
+               sin->sin_addr.s_addr = INADDR_LOOPBACK;
+       ai->ai_addr = (struct sockaddr *)sin;
+       ai->ai_next = 0;
+       return 0;
+}
+
+static void WSAAPI freeaddrinfo_stub(struct addrinfo *res)
+{
+       free(res->ai_canonname);
+       free(res->ai_addr);
+       free(res);
+}
+
+static int WSAAPI getnameinfo_stub(const struct sockaddr *sa, socklen_t salen,
+                                  char *host, DWORD hostlen,
+                                  char *serv, DWORD servlen, int flags)
+{
+       const struct sockaddr_in *sin = (const struct sockaddr_in *)sa;
+       if (sa->sa_family != AF_INET)
+               return EAI_FAMILY;
+       if (!host && !serv)
+               return EAI_NONAME;
+
+       if (host && hostlen > 0) {
+               struct hostent *ent = NULL;
+               if (!(flags & NI_NUMERICHOST))
+                       ent = gethostbyaddr((const char *)&sin->sin_addr,
+                                           sizeof(sin->sin_addr), AF_INET);
+
+               if (ent)
+                       snprintf(host, hostlen, "%s", ent->h_name);
+               else if (flags & NI_NAMEREQD)
+                       return EAI_NONAME;
+               else
+                       snprintf(host, hostlen, "%s", inet_ntoa(sin->sin_addr));
+       }
+
+       if (serv && servlen > 0) {
+               struct servent *ent = NULL;
+               if (!(flags & NI_NUMERICSERV))
+                       ent = getservbyport(sin->sin_port,
+                                           flags & NI_DGRAM ? "udp" : "tcp");
+
+               if (ent)
+                       snprintf(serv, servlen, "%s", ent->s_name);
+               else
+                       snprintf(serv, servlen, "%d", ntohs(sin->sin_port));
+       }
+
+       return 0;
+}
+
+static HMODULE ipv6_dll = NULL;
+static void (WSAAPI *ipv6_freeaddrinfo)(struct addrinfo *res);
+static int (WSAAPI *ipv6_getaddrinfo)(const char *node, const char *service,
+                                     const struct addrinfo *hints,
+                                     struct addrinfo **res);
+static int (WSAAPI *ipv6_getnameinfo)(const struct sockaddr *sa, socklen_t salen,
+                                     char *host, DWORD hostlen,
+                                     char *serv, DWORD servlen, int flags);
+/*
+ * gai_strerror is an inline function in the ws2tcpip.h header, so we
+ * don't need to try to load that one dynamically.
+ */
+
+static void socket_cleanup(void)
+{
+       WSACleanup();
+       if (ipv6_dll)
+               FreeLibrary(ipv6_dll);
+       ipv6_dll = NULL;
+       ipv6_freeaddrinfo = freeaddrinfo_stub;
+       ipv6_getaddrinfo = getaddrinfo_stub;
+       ipv6_getnameinfo = getnameinfo_stub;
+}
+
+static void ensure_socket_initialization(void)
 {
        WSADATA wsa;
+       static int initialized = 0;
+       const char *libraries[] = { "ws2_32.dll", "wship6.dll", NULL };
+       const char **name;
+
+       if (initialized)
+               return;
 
        if (WSAStartup(MAKEWORD(2,2), &wsa))
                die("unable to initialize winsock subsystem, error %d",
                        WSAGetLastError());
-       atexit((void(*)(void)) WSACleanup);
+
+       for (name = libraries; *name; name++) {
+               ipv6_dll = LoadLibrary(*name);
+               if (!ipv6_dll)
+                       continue;
+
+               ipv6_freeaddrinfo = (void (WSAAPI *)(struct addrinfo *))
+                       GetProcAddress(ipv6_dll, "freeaddrinfo");
+               ipv6_getaddrinfo = (int (WSAAPI *)(const char *, const char *,
+                                                  const struct addrinfo *,
+                                                  struct addrinfo **))
+                       GetProcAddress(ipv6_dll, "getaddrinfo");
+               ipv6_getnameinfo = (int (WSAAPI *)(const struct sockaddr *,
+                                                  socklen_t, char *, DWORD,
+                                                  char *, DWORD, int))
+                       GetProcAddress(ipv6_dll, "getnameinfo");
+               if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
+                       FreeLibrary(ipv6_dll);
+                       ipv6_dll = NULL;
+               } else
+                       break;
+       }
+       if (!ipv6_freeaddrinfo || !ipv6_getaddrinfo || !ipv6_getnameinfo) {
+               ipv6_freeaddrinfo = freeaddrinfo_stub;
+               ipv6_getaddrinfo = getaddrinfo_stub;
+               ipv6_getnameinfo = getnameinfo_stub;
+       }
+
+       atexit(socket_cleanup);
+       initialized = 1;
+}
+
+#undef gethostbyname
+struct hostent *mingw_gethostbyname(const char *host)
+{
+       ensure_socket_initialization();
        return gethostbyname(host);
 }
 
+void mingw_freeaddrinfo(struct addrinfo *res)
+{
+       ipv6_freeaddrinfo(res);
+}
+
+int mingw_getaddrinfo(const char *node, const char *service,
+                     const struct addrinfo *hints, struct addrinfo **res)
+{
+       ensure_socket_initialization();
+       return ipv6_getaddrinfo(node, service, hints, res);
+}
+
+int mingw_getnameinfo(const struct sockaddr *sa, socklen_t salen,
+                     char *host, DWORD hostlen, char *serv, DWORD servlen,
+                     int flags)
+{
+       ensure_socket_initialization();
+       return ipv6_getnameinfo(sa, salen, host, hostlen, serv, servlen, flags);
+}
+
 int mingw_socket(int domain, int type, int protocol)
 {
        int sockfd;
-       SOCKET s = WSASocket(domain, type, protocol, NULL, 0, 0);
+       SOCKET s;
+
+       ensure_socket_initialization();
+       s = WSASocket(domain, type, protocol, NULL, 0, 0);
        if (s == INVALID_SOCKET) {
                /*
                 * WSAGetLastError() values are regular BSD error codes
@@ -949,6 +1205,45 @@ int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
        return connect(s, sa, sz);
 }
 
+#undef bind
+int mingw_bind(int sockfd, struct sockaddr *sa, size_t sz)
+{
+       SOCKET s = (SOCKET)_get_osfhandle(sockfd);
+       return bind(s, sa, sz);
+}
+
+#undef setsockopt
+int mingw_setsockopt(int sockfd, int lvl, int optname, void *optval, int optlen)
+{
+       SOCKET s = (SOCKET)_get_osfhandle(sockfd);
+       return setsockopt(s, lvl, optname, (const char*)optval, optlen);
+}
+
+#undef listen
+int mingw_listen(int sockfd, int backlog)
+{
+       SOCKET s = (SOCKET)_get_osfhandle(sockfd);
+       return listen(s, backlog);
+}
+
+#undef accept
+int mingw_accept(int sockfd1, struct sockaddr *sa, socklen_t *sz)
+{
+       int sockfd2;
+
+       SOCKET s1 = (SOCKET)_get_osfhandle(sockfd1);
+       SOCKET s2 = accept(s1, sa, sz);
+
+       /* convert into a file descriptor */
+       if ((sockfd2 = _open_osfhandle(s2, O_RDWR|O_BINARY)) < 0) {
+               int err = errno;
+               closesocket(s2);
+               return error("unable to make a socket file descriptor: %s",
+                       strerror(err));
+       }
+       return sockfd2;
+}
+
 #undef rename
 int mingw_rename(const char *pold, const char *pnew)
 {
@@ -1000,6 +1295,18 @@ repeat:
        return -1;
 }
 
+/*
+ * Note that this doesn't return the actual pagesize, but
+ * the allocation granularity. If future Windows specific git code
+ * needs the real getpagesize function, we need to find another solution.
+ */
+int mingw_getpagesize(void)
+{
+       SYSTEM_INFO si;
+       GetSystemInfo(&si);
+       return si.dwAllocationGranularity;
+}
+
 struct passwd *getpwuid(int uid)
 {
        static char user_name[100];
@@ -1150,8 +1457,26 @@ static const char *make_backslash_path(const char *path)
 void mingw_open_html(const char *unixpath)
 {
        const char *htmlpath = make_backslash_path(unixpath);
+       typedef HINSTANCE (WINAPI *T)(HWND, const char *,
+                       const char *, const char *, const char *, INT);
+       T ShellExecute;
+       HMODULE shell32;
+       int r;
+
+       shell32 = LoadLibrary("shell32.dll");
+       if (!shell32)
+               die("cannot load shell32.dll");
+       ShellExecute = (T)GetProcAddress(shell32, "ShellExecuteA");
+       if (!ShellExecute)
+               die("cannot run browser");
+
        printf("Launching default browser to display HTML ...\n");
-       ShellExecute(NULL, "open", htmlpath, NULL, "\\", 0);
+       r = (int)ShellExecute(NULL, "open", htmlpath, NULL, "\\", SW_SHOWNORMAL);
+       FreeLibrary(shell32);
+       /* see the MSDN documentation referring to the result codes here */
+       if (r <= 32) {
+               die("failed to launch browser for %.*s", MAX_PATH, unixpath);
+       }
 }
 
 int link(const char *oldpath, const char *newpath)
@@ -1190,62 +1515,54 @@ char *getpass(const char *prompt)
        return strbuf_detach(&buf, NULL);
 }
 
-#ifndef NO_MINGW_REPLACE_READDIR
-/* MinGW readdir implementation to avoid extra lstats for Git */
-struct mingw_DIR
-{
-       struct _finddata_t      dd_dta;         /* disk transfer area for this dir */
-       struct mingw_dirent     dd_dir;         /* Our own implementation, including d_type */
-       long                    dd_handle;      /* _findnext handle */
-       int                     dd_stat;        /* 0 = next entry to read is first entry, -1 = off the end, positive = 0 based index of next entry */
-       char                    dd_name[1];     /* given path for dir with search pattern (struct is extended) */
-};
-
-struct dirent *mingw_readdir(DIR *dir)
+pid_t waitpid(pid_t pid, int *status, unsigned options)
 {
-       WIN32_FIND_DATAA buf;
-       HANDLE handle;
-       struct mingw_DIR *mdir = (struct mingw_DIR*)dir;
-
-       if (!dir->dd_handle) {
-               errno = EBADF; /* No set_errno for mingw */
-               return NULL;
+       HANDLE h = OpenProcess(SYNCHRONIZE | PROCESS_QUERY_INFORMATION,
+           FALSE, pid);
+       if (!h) {
+               errno = ECHILD;
+               return -1;
        }
 
-       if (dir->dd_handle == (long)INVALID_HANDLE_VALUE && dir->dd_stat == 0)
-       {
-               DWORD lasterr;
-               handle = FindFirstFileA(dir->dd_name, &buf);
-               lasterr = GetLastError();
-               dir->dd_handle = (long)handle;
-               if (handle == INVALID_HANDLE_VALUE && (lasterr != ERROR_NO_MORE_FILES)) {
-                       errno = err_win_to_posix(lasterr);
-                       return NULL;
+       if (pid > 0 && options & WNOHANG) {
+               if (WAIT_OBJECT_0 != WaitForSingleObject(h, 0)) {
+                       CloseHandle(h);
+                       return 0;
                }
-       } else if (dir->dd_handle == (long)INVALID_HANDLE_VALUE) {
-               return NULL;
-       } else if (!FindNextFileA((HANDLE)dir->dd_handle, &buf)) {
-               DWORD lasterr = GetLastError();
-               FindClose((HANDLE)dir->dd_handle);
-               dir->dd_handle = (long)INVALID_HANDLE_VALUE;
-               /* POSIX says you shouldn't set errno when readdir can't
-                  find any more files; so, if another error we leave it set. */
-               if (lasterr != ERROR_NO_MORE_FILES)
-                       errno = err_win_to_posix(lasterr);
-               return NULL;
+               options &= ~WNOHANG;
        }
 
-       /* We get here if `buf' contains valid data.  */
-       strcpy(dir->dd_dir.d_name, buf.cFileName);
-       ++dir->dd_stat;
+       if (options == 0) {
+               struct pinfo_t **ppinfo;
+               if (WaitForSingleObject(h, INFINITE) != WAIT_OBJECT_0) {
+                       CloseHandle(h);
+                       return 0;
+               }
+
+               if (status)
+                       GetExitCodeProcess(h, (LPDWORD)status);
 
-       /* Set file type, based on WIN32_FIND_DATA */
-       mdir->dd_dir.d_type = 0;
-       if (buf.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
-               mdir->dd_dir.d_type |= DT_DIR;
-       else
-               mdir->dd_dir.d_type |= DT_REG;
+               EnterCriticalSection(&pinfo_cs);
+
+               ppinfo = &pinfo;
+               while (*ppinfo) {
+                       struct pinfo_t *info = *ppinfo;
+                       if (info->pid == pid) {
+                               CloseHandle(info->proc);
+                               *ppinfo = info->next;
+                               free(info);
+                               break;
+                       }
+                       ppinfo = &info->next;
+               }
+
+               LeaveCriticalSection(&pinfo_cs);
 
-       return (struct dirent*)&dir->dd_dir;
+               CloseHandle(h);
+               return pid;
+       }
+       CloseHandle(h);
+
+       errno = EINVAL;
+       return -1;
 }
-#endif // !NO_MINGW_REPLACE_READDIR