Merge branch 'kh/diff-tree'
[gitweb.git] / compat / mingw.c
index 4e559bdc93dbee413fd574168fd382e4682a0092..ccfa2a0a3d3263862beb0d2796be1aba78574986 100644 (file)
@@ -1,7 +1,187 @@
 #include "../git-compat-util.h"
+#include "../strbuf.h"
 
 unsigned int _CRT_fmode = _O_BINARY;
 
+#undef open
+int mingw_open (const char *filename, int oflags, ...)
+{
+       va_list args;
+       unsigned mode;
+       va_start(args, oflags);
+       mode = va_arg(args, int);
+       va_end(args);
+
+       if (!strcmp(filename, "/dev/null"))
+               filename = "nul";
+       int fd = open(filename, oflags, mode);
+       if (fd < 0 && (oflags & O_CREAT) && errno == EACCES) {
+               DWORD attrs = GetFileAttributes(filename);
+               if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY))
+                       errno = EISDIR;
+       }
+       return fd;
+}
+
+static inline time_t filetime_to_time_t(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;
+}
+
+extern int _getdrive( void );
+/* 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.
+ */
+static int do_lstat(const char *file_name, struct stat *buf)
+{
+       WIN32_FILE_ATTRIBUTE_DATA fdata;
+
+       if (GetFileAttributesExA(file_name, GetFileExInfoStandard, &fdata)) {
+               int fMode = S_IREAD;
+               if (fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
+                       fMode |= S_IFDIR;
+               else
+                       fMode |= S_IFREG;
+               if (!(fdata.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
+                       fMode |= S_IWRITE;
+
+               buf->st_ino = 0;
+               buf->st_gid = 0;
+               buf->st_uid = 0;
+               buf->st_nlink = 1;
+               buf->st_mode = fMode;
+               buf->st_size = fdata.nFileSizeLow; /* Can't use nFileSizeHigh, since it's not a stat64 */
+               buf->st_dev = buf->st_rdev = (_getdrive() - 1);
+               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));
+               errno = 0;
+               return 0;
+       }
+
+       switch (GetLastError()) {
+       case ERROR_ACCESS_DENIED:
+       case ERROR_SHARING_VIOLATION:
+       case ERROR_LOCK_VIOLATION:
+       case ERROR_SHARING_BUFFER_EXCEEDED:
+               errno = EACCES;
+               break;
+       case ERROR_BUFFER_OVERFLOW:
+               errno = ENAMETOOLONG;
+               break;
+       case ERROR_NOT_ENOUGH_MEMORY:
+               errno = ENOMEM;
+               break;
+       default:
+               errno = ENOENT;
+               break;
+       }
+       return -1;
+}
+
+/* We provide our own lstat/fstat functions, since the provided
+ * lstat/fstat functions are so slow. These stat functions are
+ * tailored for Git's usage (read: fast), and are not meant to be
+ * 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)
+{
+       int namelen;
+       static char alt_name[PATH_MAX];
+
+       if (!do_lstat(file_name, buf))
+               return 0;
+
+       /* if file_name ended in a '/', Windows returned ENOENT;
+        * try again without trailing slashes
+        */
+       if (errno != ENOENT)
+               return -1;
+
+       namelen = strlen(file_name);
+       if (namelen && file_name[namelen-1] != '/')
+               return -1;
+       while (namelen && file_name[namelen-1] == '/')
+               --namelen;
+       if (!namelen || namelen >= PATH_MAX)
+               return -1;
+
+       memcpy(alt_name, file_name, namelen);
+       alt_name[namelen] = 0;
+       return do_lstat(alt_name, buf);
+}
+
+#undef fstat
+int mingw_fstat(int fd, struct stat *buf)
+{
+       HANDLE fh = (HANDLE)_get_osfhandle(fd);
+       BY_HANDLE_FILE_INFORMATION fdata;
+
+       if (fh == INVALID_HANDLE_VALUE) {
+               errno = EBADF;
+               return -1;
+       }
+       /* direct non-file handles to MS's fstat() */
+       if (GetFileType(fh) != FILE_TYPE_DISK)
+               return fstat(fd, buf);
+
+       if (GetFileInformationByHandle(fh, &fdata)) {
+               int fMode = S_IREAD;
+               if (fdata.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY)
+                       fMode |= S_IFDIR;
+               else
+                       fMode |= S_IFREG;
+               if (!(fdata.dwFileAttributes & FILE_ATTRIBUTE_READONLY))
+                       fMode |= S_IWRITE;
+
+               buf->st_ino = 0;
+               buf->st_gid = 0;
+               buf->st_uid = 0;
+               buf->st_nlink = 1;
+               buf->st_mode = fMode;
+               buf->st_size = fdata.nFileSizeLow; /* Can't use nFileSizeHigh, since it's not a stat64 */
+               buf->st_dev = buf->st_rdev = (_getdrive() - 1);
+               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));
+               return 0;
+       }
+       errno = EBADF;
+       return -1;
+}
+
+static inline void time_t_to_filetime(time_t t, FILETIME *ft)
+{
+       long long winTime = t * 10000000LL + 116444736000000000LL;
+       ft->dwLowDateTime = winTime;
+       ft->dwHighDateTime = winTime >> 32;
+}
+
+int mingw_utime (const char *file_name, const struct utimbuf *times)
+{
+       FILETIME mft, aft;
+       int fh, rc;
+
+       /* must have write permission */
+       if ((fh = open(file_name, O_RDWR | O_BINARY)) < 0)
+               return -1;
+
+       time_t_to_filetime(times->modtime, &mft);
+       time_t_to_filetime(times->actime, &aft);
+       if (!SetFileTime((HANDLE)_get_osfhandle(fh), NULL, &aft, &mft)) {
+               errno = EINVAL;
+               rc = -1;
+       } else
+               rc = 0;
+       close(fh);
+       return rc;
+}
+
 unsigned int sleep (unsigned int seconds)
 {
        Sleep(seconds*1000);
@@ -18,12 +198,125 @@ int mkstemp(char *template)
 
 int gettimeofday(struct timeval *tv, void *tz)
 {
-       return -1;
+       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;
+       return 0;
+}
+
+int pipe(int filedes[2])
+{
+       int fd;
+       HANDLE h[2], parent;
+
+       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]);
+               return -1;
+       }
+       fd = _open_osfhandle((int)h[0], O_NOINHERIT);
+       if (fd < 0) {
+               close(filedes[0]);
+               close(filedes[1]);
+               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) {
+               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)
 {
-       return -1;
+       int i, pending;
+
+       if (timeout != -1)
+               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
+                * relinguishing here.
+                */
+               Sleep(0);
+               goto repeat;
+       }
+       return 0;
 }
 
 struct tm *gmtime_r(const time_t *timep, struct tm *result)
@@ -53,18 +346,677 @@ char *mingw_getcwd(char *pointer, int len)
        return ret;
 }
 
+#undef getenv
+char *mingw_getenv(const char *name)
+{
+       char *result = getenv(name);
+       if (!result && !strcmp(name, "TMPDIR")) {
+               /* on Windows it is TMP and TEMP */
+               result = getenv("TMP");
+               if (!result)
+                       result = getenv("TEMP");
+       }
+       return result;
+}
+
+/*
+ * See http://msdn2.microsoft.com/en-us/library/17w5ykft(vs.71).aspx
+ * (Parsing C++ Command-Line Arguments)
+ */
+static const char *quote_arg(const char *arg)
+{
+       /* count chars to quote */
+       int len = 0, n = 0;
+       int force_quotes = 0;
+       char *q, *d;
+       const char *p = arg;
+       if (!*p) force_quotes = 1;
+       while (*p) {
+               if (isspace(*p) || *p == '*' || *p == '?' || *p == '{')
+                       force_quotes = 1;
+               else if (*p == '"')
+                       n++;
+               else if (*p == '\\') {
+                       int count = 0;
+                       while (*p == '\\') {
+                               count++;
+                               p++;
+                               len++;
+                       }
+                       if (*p == '"')
+                               n += count*2 + 1;
+                       continue;
+               }
+               len++;
+               p++;
+       }
+       if (!force_quotes && n == 0)
+               return arg;
+
+       /* insert \ where necessary */
+       d = q = xmalloc(len+n+3);
+       *d++ = '"';
+       while (*arg) {
+               if (*arg == '"')
+                       *d++ = '\\';
+               else if (*arg == '\\') {
+                       int count = 0;
+                       while (*arg == '\\') {
+                               count++;
+                               *d++ = *arg++;
+                       }
+                       if (*arg == '"') {
+                               while (count-- > 0)
+                                       *d++ = '\\';
+                               *d++ = '\\';
+                       }
+               }
+               *d++ = *arg++;
+       }
+       *d++ = '"';
+       *d++ = 0;
+       return q;
+}
+
+static const char *parse_interpreter(const char *cmd)
+{
+       static char buf[100];
+       char *p, *opt;
+       int n, fd;
+
+       /* don't even try a .exe */
+       n = strlen(cmd);
+       if (n >= 4 && !strcasecmp(cmd+n-4, ".exe"))
+               return NULL;
+
+       fd = open(cmd, O_RDONLY);
+       if (fd < 0)
+               return NULL;
+       n = read(fd, buf, sizeof(buf)-1);
+       close(fd);
+       if (n < 4)      /* at least '#!/x' and not error */
+               return NULL;
+
+       if (buf[0] != '#' || buf[1] != '!')
+               return NULL;
+       buf[n] = '\0';
+       p = strchr(buf, '\n');
+       if (!p)
+               return NULL;
+
+       *p = '\0';
+       if (!(p = strrchr(buf+2, '/')) && !(p = strrchr(buf+2, '\\')))
+               return NULL;
+       /* strip options */
+       if ((opt = strchr(p+1, ' ')))
+               *opt = '\0';
+       return p+1;
+}
+
+/*
+ * Splits the PATH into parts.
+ */
+static char **get_path_split(void)
+{
+       char *p, **path, *envpath = getenv("PATH");
+       int i, n = 0;
+
+       if (!envpath || !*envpath)
+               return NULL;
+
+       envpath = xstrdup(envpath);
+       p = envpath;
+       while (p) {
+               char *dir = p;
+               p = strchr(p, ';');
+               if (p) *p++ = '\0';
+               if (*dir) {     /* not earlier, catches series of ; */
+                       ++n;
+               }
+       }
+       if (!n)
+               return NULL;
+
+       path = xmalloc((n+1)*sizeof(char*));
+       p = envpath;
+       i = 0;
+       do {
+               if (*p)
+                       path[i++] = xstrdup(p);
+               p = p+strlen(p)+1;
+       } while (i < n);
+       path[i] = NULL;
+
+       free(envpath);
+
+       return path;
+}
+
+static void free_path_split(char **path)
+{
+       if (!path)
+               return;
+
+       char **p = path;
+       while (*p)
+               free(*p++);
+       free(path);
+}
+
+/*
+ * exe_only means that we only want to detect .exe files, but not scripts
+ * (which do not have an extension)
+ */
+static char *lookup_prog(const char *dir, const char *cmd, int isexe, int exe_only)
+{
+       char path[MAX_PATH];
+       snprintf(path, sizeof(path), "%s/%s.exe", dir, cmd);
+
+       if (!isexe && access(path, F_OK) == 0)
+               return xstrdup(path);
+       path[strlen(path)-4] = '\0';
+       if ((!exe_only || isexe) && access(path, F_OK) == 0)
+               if (!(GetFileAttributes(path) & FILE_ATTRIBUTE_DIRECTORY))
+                       return xstrdup(path);
+       return NULL;
+}
+
+/*
+ * Determines the absolute path of cmd using the 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)
+{
+       char *prog = NULL;
+       int len = strlen(cmd);
+       int isexe = len >= 4 && !strcasecmp(cmd+len-4, ".exe");
+
+       if (strchr(cmd, '/') || strchr(cmd, '\\'))
+               prog = xstrdup(cmd);
+
+       while (!prog && *path)
+               prog = lookup_prog(*path++, cmd, isexe, exe_only);
+
+       return prog;
+}
+
+static int env_compare(const void *a, const void *b)
+{
+       char *const *ea = a;
+       char *const *eb = b;
+       return strcasecmp(*ea, *eb);
+}
+
+static pid_t mingw_spawnve(const char *cmd, const char **argv, char **env,
+                          int prepend_cmd)
+{
+       STARTUPINFO si;
+       PROCESS_INFORMATION pi;
+       struct strbuf envblk, args;
+       unsigned flags;
+       BOOL ret;
+
+       /* Determine whether or not we are associated to a console */
+       HANDLE cons = CreateFile("CONOUT$", GENERIC_WRITE,
+                       FILE_SHARE_WRITE, NULL, OPEN_EXISTING,
+                       FILE_ATTRIBUTE_NORMAL, NULL);
+       if (cons == INVALID_HANDLE_VALUE) {
+               /* There is no console associated with this process.
+                * Since the child is a console process, Windows
+                * would normally create a console window. But
+                * since we'll be redirecting std streams, we do
+                * not need the console.
+                */
+               flags = CREATE_NO_WINDOW;
+       } else {
+               /* There is already a console. If we specified
+                * CREATE_NO_WINDOW here, too, Windows would
+                * disassociate the child from the console.
+                * Go figure!
+                */
+               flags = 0;
+               CloseHandle(cons);
+       }
+       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);
+
+       /* concatenate argv, quoting args as we go */
+       strbuf_init(&args, 0);
+       if (prepend_cmd) {
+               char *quoted = (char *)quote_arg(cmd);
+               strbuf_addstr(&args, quoted);
+               if (quoted != cmd)
+                       free(quoted);
+       }
+       for (; *argv; argv++) {
+               char *quoted = (char *)quote_arg(*argv);
+               if (*args.buf)
+                       strbuf_addch(&args, ' ');
+               strbuf_addstr(&args, quoted);
+               if (quoted != *argv)
+                       free(quoted);
+       }
+
+       if (env) {
+               int count = 0;
+               char **e, **sorted_env;
+
+               for (e = env; *e; e++)
+                       count++;
+
+               /* environment must be sorted */
+               sorted_env = xmalloc(sizeof(*sorted_env) * (count + 1));
+               memcpy(sorted_env, env, sizeof(*sorted_env) * (count + 1));
+               qsort(sorted_env, count, sizeof(*sorted_env), env_compare);
+
+               strbuf_init(&envblk, 0);
+               for (e = sorted_env; *e; e++) {
+                       strbuf_addstr(&envblk, *e);
+                       strbuf_addch(&envblk, '\0');
+               }
+               free(sorted_env);
+       }
+
+       memset(&pi, 0, sizeof(pi));
+       ret = CreateProcess(cmd, args.buf, NULL, NULL, TRUE, flags,
+               env ? envblk.buf : NULL, NULL, &si, &pi);
+
+       if (env)
+               strbuf_release(&envblk);
+       strbuf_release(&args);
+
+       if (!ret) {
+               errno = ENOENT;
+               return -1;
+       }
+       CloseHandle(pi.hThread);
+       return (pid_t)pi.hProcess;
+}
+
+pid_t mingw_spawnvpe(const char *cmd, const char **argv, char **env)
+{
+       pid_t pid;
+       char **path = get_path_split();
+       char *prog = path_lookup(cmd, path, 0);
+
+       if (!prog) {
+               errno = ENOENT;
+               pid = -1;
+       }
+       else {
+               const char *interpr = parse_interpreter(prog);
+
+               if (interpr) {
+                       const char *argv0 = argv[0];
+                       char *iprog = path_lookup(interpr, path, 1);
+                       argv[0] = prog;
+                       if (!iprog) {
+                               errno = ENOENT;
+                               pid = -1;
+                       }
+                       else {
+                               pid = mingw_spawnve(iprog, argv, env, 1);
+                               free(iprog);
+                       }
+                       argv[0] = argv0;
+               }
+               else
+                       pid = mingw_spawnve(prog, argv, env, 0);
+               free(prog);
+       }
+       free_path_split(path);
+       return pid;
+}
+
+static int try_shell_exec(const char *cmd, char *const *argv, char **env)
+{
+       const char *interpr = parse_interpreter(cmd);
+       char **path;
+       char *prog;
+       int pid = 0;
+
+       if (!interpr)
+               return 0;
+       path = get_path_split();
+       prog = path_lookup(interpr, path, 1);
+       if (prog) {
+               int argc = 0;
+               const char **argv2;
+               while (argv[argc]) argc++;
+               argv2 = xmalloc(sizeof(*argv) * (argc+1));
+               argv2[0] = (char *)cmd; /* full path to the script file */
+               memcpy(&argv2[1], &argv[1], sizeof(*argv) * argc);
+               pid = mingw_spawnve(prog, argv2, env, 1);
+               if (pid >= 0) {
+                       int status;
+                       if (waitpid(pid, &status, 0) < 0)
+                               status = 255;
+                       exit(status);
+               }
+               pid = 1;        /* indicate that we tried but failed */
+               free(prog);
+               free(argv2);
+       }
+       free_path_split(path);
+       return pid;
+}
+
+static void mingw_execve(const char *cmd, char *const *argv, char *const *env)
+{
+       /* check if git_command is a shell script */
+       if (!try_shell_exec(cmd, argv, (char **)env)) {
+               int pid, status;
+
+               pid = mingw_spawnve(cmd, (const char **)argv, (char **)env, 0);
+               if (pid < 0)
+                       return;
+               if (waitpid(pid, &status, 0) < 0)
+                       status = 255;
+               exit(status);
+       }
+}
+
+void mingw_execvp(const char *cmd, char *const *argv)
+{
+       char **path = get_path_split();
+       char *prog = path_lookup(cmd, path, 0);
+
+       if (prog) {
+               mingw_execve(prog, argv, environ);
+               free(prog);
+       } else
+               errno = ENOENT;
+
+       free_path_split(path);
+}
+
+char **copy_environ()
+{
+       char **env;
+       int i = 0;
+       while (environ[i])
+               i++;
+       env = xmalloc((i+1)*sizeof(*env));
+       for (i = 0; environ[i]; i++)
+               env[i] = xstrdup(environ[i]);
+       env[i] = NULL;
+       return env;
+}
+
+void free_environ(char **env)
+{
+       int i;
+       for (i = 0; env[i]; i++)
+               free(env[i]);
+       free(env);
+}
+
+static int lookup_env(char **env, const char *name, size_t nmln)
+{
+       int i;
+
+       for (i = 0; env[i]; i++) {
+               if (0 == strncmp(env[i], name, nmln)
+                   && '=' == env[i][nmln])
+                       /* matches */
+                       return i;
+       }
+       return -1;
+}
+
+/*
+ * If name contains '=', then sets the variable, otherwise it unsets it
+ */
+char **env_setenv(char **env, const char *name)
+{
+       char *eq = strchrnul(name, '=');
+       int i = lookup_env(env, name, eq-name);
+
+       if (i < 0) {
+               if (*eq) {
+                       for (i = 0; env[i]; i++)
+                               ;
+                       env = xrealloc(env, (i+2)*sizeof(*env));
+                       env[i] = xstrdup(name);
+                       env[i+1] = NULL;
+               }
+       }
+       else {
+               free(env[i]);
+               if (*eq)
+                       env[i] = xstrdup(name);
+               else
+                       for (; env[i]; i++)
+                               env[i] = env[i+1];
+       }
+       return env;
+}
+
+/* this is the first function to call into WS_32; initialize it */
+#undef gethostbyname
+struct hostent *mingw_gethostbyname(const char *host)
+{
+       WSADATA wsa;
+
+       if (WSAStartup(MAKEWORD(2,2), &wsa))
+               die("unable to initialize winsock subsystem, error %d",
+                       WSAGetLastError());
+       atexit((void(*)(void)) WSACleanup);
+       return gethostbyname(host);
+}
+
+int mingw_socket(int domain, int type, int protocol)
+{
+       int sockfd;
+       SOCKET s = WSASocket(domain, type, protocol, NULL, 0, 0);
+       if (s == INVALID_SOCKET) {
+               /*
+                * WSAGetLastError() values are regular BSD error codes
+                * biased by WSABASEERR.
+                * However, strerror() does not know about networking
+                * specific errors, which are values beginning at 38 or so.
+                * Therefore, we choose to leave the biased error code
+                * in errno so that _if_ someone looks up the code somewhere,
+                * then it is at least the number that are usually listed.
+                */
+               errno = WSAGetLastError();
+               return -1;
+       }
+       /* convert into a file descriptor */
+       if ((sockfd = _open_osfhandle(s, O_RDWR|O_BINARY)) < 0) {
+               closesocket(s);
+               return error("unable to make a socket file descriptor: %s",
+                       strerror(errno));
+       }
+       return sockfd;
+}
+
+#undef connect
+int mingw_connect(int sockfd, struct sockaddr *sa, size_t sz)
+{
+       SOCKET s = (SOCKET)_get_osfhandle(sockfd);
+       return connect(s, sa, sz);
+}
+
+#undef rename
+int mingw_rename(const char *pold, const char *pnew)
+{
+       /*
+        * Try native rename() first to get errno right.
+        * It is based on MoveFile(), which cannot overwrite existing files.
+        */
+       if (!rename(pold, pnew))
+               return 0;
+       if (errno != EEXIST)
+               return -1;
+       if (MoveFileEx(pold, pnew, MOVEFILE_REPLACE_EXISTING))
+               return 0;
+       /* TODO: translate more errors */
+       if (GetLastError() == ERROR_ACCESS_DENIED) {
+               DWORD attrs = GetFileAttributes(pnew);
+               if (attrs != INVALID_FILE_ATTRIBUTES && (attrs & FILE_ATTRIBUTE_DIRECTORY)) {
+                       errno = EISDIR;
+                       return -1;
+               }
+       }
+       errno = EACCES;
+       return -1;
+}
+
 struct passwd *getpwuid(int uid)
 {
+       static char user_name[100];
        static struct passwd p;
+
+       DWORD len = sizeof(user_name);
+       if (!GetUserName(user_name, &len))
+               return NULL;
+       p.pw_name = user_name;
+       p.pw_gecos = "unknown";
+       p.pw_dir = NULL;
        return &p;
 }
 
+static HANDLE timer_event;
+static HANDLE timer_thread;
+static int timer_interval;
+static int one_shot;
+static sig_handler_t timer_fn = SIG_DFL;
+
+/* The timer works like this:
+ * The thread, ticktack(), is a trivial routine that most of the time
+ * only waits to receive the signal to terminate. The main thread tells
+ * the thread to terminate by setting the timer_event to the signalled
+ * state.
+ * But ticktack() interrupts the wait state after the timer's interval
+ * length to call the signal handler.
+ */
+
+static __stdcall unsigned ticktack(void *dummy)
+{
+       while (WaitForSingleObject(timer_event, timer_interval) == WAIT_TIMEOUT) {
+               if (timer_fn == SIG_DFL)
+                       die("Alarm");
+               if (timer_fn != SIG_IGN)
+                       timer_fn(SIGALRM);
+               if (one_shot)
+                       break;
+       }
+       return 0;
+}
+
+static int start_timer_thread(void)
+{
+       timer_event = CreateEvent(NULL, FALSE, FALSE, NULL);
+       if (timer_event) {
+               timer_thread = (HANDLE) _beginthreadex(NULL, 0, ticktack, NULL, 0, NULL);
+               if (!timer_thread )
+                       return errno = ENOMEM,
+                               error("cannot start timer thread");
+       } else
+               return errno = ENOMEM,
+                       error("cannot allocate resources for timer");
+       return 0;
+}
+
+static void stop_timer_thread(void)
+{
+       if (timer_event)
+               SetEvent(timer_event);  /* tell thread to terminate */
+       if (timer_thread) {
+               int rc = WaitForSingleObject(timer_thread, 1000);
+               if (rc == WAIT_TIMEOUT)
+                       error("timer thread did not terminate timely");
+               else if (rc != WAIT_OBJECT_0)
+                       error("waiting for timer thread failed: %lu",
+                             GetLastError());
+               CloseHandle(timer_thread);
+       }
+       if (timer_event)
+               CloseHandle(timer_event);
+       timer_event = NULL;
+       timer_thread = NULL;
+}
+
+static inline int is_timeval_eq(const struct timeval *i1, const struct timeval *i2)
+{
+       return i1->tv_sec == i2->tv_sec && i1->tv_usec == i2->tv_usec;
+}
+
 int setitimer(int type, struct itimerval *in, struct itimerval *out)
 {
-       return -1;
+       static const struct timeval zero;
+       static int atexit_done;
+
+       if (out != NULL)
+               return errno = EINVAL,
+                       error("setitimer param 3 != NULL not implemented");
+       if (!is_timeval_eq(&in->it_interval, &zero) &&
+           !is_timeval_eq(&in->it_interval, &in->it_value))
+               return errno = EINVAL,
+                       error("setitimer: it_interval must be zero or eq it_value");
+
+       if (timer_thread)
+               stop_timer_thread();
+
+       if (is_timeval_eq(&in->it_value, &zero) &&
+           is_timeval_eq(&in->it_interval, &zero))
+               return 0;
+
+       timer_interval = in->it_value.tv_sec * 1000 + in->it_value.tv_usec / 1000;
+       one_shot = is_timeval_eq(&in->it_interval, &zero);
+       if (!atexit_done) {
+               atexit(stop_timer_thread);
+               atexit_done = 1;
+       }
+       return start_timer_thread();
 }
 
 int sigaction(int sig, struct sigaction *in, struct sigaction *out)
 {
-       return -1;
+       if (sig != SIGALRM)
+               return errno = EINVAL,
+                       error("sigaction only implemented for SIGALRM");
+       if (out != NULL)
+               return errno = EINVAL,
+                       error("sigaction: param 3 != NULL not implemented");
+
+       timer_fn = in->sa_handler;
+       return 0;
+}
+
+#undef signal
+sig_handler_t mingw_signal(int sig, sig_handler_t handler)
+{
+       if (sig != SIGALRM)
+               return signal(sig, handler);
+       sig_handler_t old = timer_fn;
+       timer_fn = handler;
+       return old;
+}
+
+static const char *make_backslash_path(const char *path)
+{
+       static char buf[PATH_MAX + 1];
+       char *c;
+
+       if (strlcpy(buf, path, PATH_MAX) >= PATH_MAX)
+               die("Too long path: %.*s", 60, path);
+
+       for (c = buf; *c; c++) {
+               if (*c == '/')
+                       *c = '\\';
+       }
+       return buf;
+}
+
+void mingw_open_html(const char *unixpath)
+{
+       const char *htmlpath = make_backslash_path(unixpath);
+       printf("Launching default browser to display HTML ...\n");
+       ShellExecute(NULL, "open", htmlpath, NULL, "\\", 0);
 }