--- /dev/null
+/* Convert file names between Cygwin syntax and Windows syntax.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+
+ This file is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation, either version 3 of the License,
+ or (at your option) any later version.
+
+ This file is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2024. */
+
+#include <config.h>
+
+/* Specification. */
+#include "cygpath.h"
+
+#include <stdlib.h>
+
+#include "xalloc.h"
+#include "gettext.h"
+
+#define _(str) gettext (str)
+
+#ifdef __CYGWIN__
+
+/* Since Cygwin has its own notion of mount points (which can be defined by the
+ user), it would be wrong to blindly convert '/cygdrive/c/foo' to 'C:\foo'.
+ We really need to use the Cygwin API or the 'cygpath' program. */
+
+# include <errno.h>
+# include <error.h>
+
+# if 1
+
+/* Documentation:
+ https://cygwin.com/cygwin-api/func-cygwin-conv-path.html */
+
+# include <sys/cygwin.h>
+
+char *
+cygpath_w (const char *filename)
+{
+ int repeat;
+
+ /* Try several times, since there is a small time window during which the
+ size returned by the previous call may not be sufficient, namely when a
+ directory gets renamed. */
+ for (repeat = 3; repeat > 0; repeat--)
+ {
+ ssize_t size = cygwin_conv_path (CCP_POSIX_TO_WIN_A | CCP_RELATIVE, filename, NULL, 0);
+ if (size < 0)
+ error (EXIT_FAILURE, errno, _("cannot convert file name '%s' to Windows syntax"), filename);
+ char *result = (char *) xmalloc (size);
+ if (cygwin_conv_path (CCP_POSIX_TO_WIN_A | CCP_RELATIVE, filename, result, size) == 0)
+ return result;
+ free (result);
+ }
+ error (EXIT_FAILURE, errno, _("cygwin_conv_path failed"));
+ return NULL;
+}
+
+# else
+/* Alternative implementation (slower) */
+
+/* Documentation:
+ https://cygwin.com/cygwin-ug-net/cygpath.html */
+
+# include <stdio.h>
+
+# include "spawn-pipe.h"
+# include "wait-process.h"
+
+/* Executes a program.
+ Returns the first line of its output, as a freshly allocated string, or
+ NULL. */
+static char *
+execute_and_read_line (const char *progname,
+ const char *prog_path, const char * const *prog_argv)
+{
+ pid_t child;
+ int fd[1];
+ FILE *fp;
+ char *line;
+ size_t linesize;
+ size_t linelen;
+
+ /* Open a pipe to the program. */
+ child = create_pipe_in (progname, prog_path, prog_argv, NULL,
+ DEV_NULL, false, true, false, fd);
+
+ if (child == -1)
+ return NULL;
+
+ /* Retrieve its result. */
+ fp = fdopen (fd[0], "r");
+ if (fp == NULL)
+ error (EXIT_FAILURE, errno, _("fdopen() failed"));
+
+ line = NULL; linesize = 0;
+ linelen = getline (&line, &linesize, fp);
+ if (linelen == (size_t)(-1))
+ {
+ error (0, 0, _("%s subprocess I/O error"), progname);
+ fclose (fp);
+ wait_subprocess (child, progname, true, false, true, false, NULL);
+ }
+ else
+ {
+ int exitstatus;
+
+ if (linelen > 0 && line[linelen - 1] == '\n')
+ line[linelen - 1] = '\0';
+
+ /* Read until EOF (otherwise the child process may get a SIGPIPE signal). */
+ while (getc (fp) != EOF)
+ ;
+
+ fclose (fp);
+
+ /* Remove zombie process from process list, and retrieve exit status. */
+ exitstatus =
+ wait_subprocess (child, progname, true, false, true, false, NULL);
+ if (exitstatus == 0)
+ return line;
+ }
+ free (line);
+ return NULL;
+}
+
+char *
+cygpath_w (const char *filename)
+{
+ const char *argv[4];
+
+ argv[0] = "cygpath";
+ argv[1] = "-w";
+ argv[2] = filename;
+ argv[3] = NULL;
+
+ char *line = execute_and_read_line ("cygpath", "cygpath", argv);
+ if (line == NULL || line[0] == '\0')
+ error (EXIT_FAILURE, 0, _("%s invocation failed"), "cygpath");
+ return line;
+}
+
+# endif
+
+#else
+
+char *
+cygpath_w (const char *filename)
+{
+ return xstrdup (filename);
+}
+
+#endif
--- /dev/null
+/* Convert file names between Cygwin syntax and Windows syntax.
+ Copyright (C) 2024 Free Software Foundation, Inc.
+
+ This file is free software: you can redistribute it and/or modify
+ it under the terms of the GNU General Public License as published
+ by the Free Software Foundation, either version 3 of the License,
+ or (at your option) any later version.
+
+ This file is distributed in the hope that it will be useful,
+ but WITHOUT ANY WARRANTY; without even the implied warranty of
+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ GNU General Public License for more details.
+
+ You should have received a copy of the GNU General Public License
+ along with this program. If not, see <https://www.gnu.org/licenses/>. */
+
+/* Written by Bruno Haible <bruno@clisp.org>, 2024. */
+
+#ifndef _CYGPATH_H
+#define _CYGPATH_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* On Cygwin, this function converts a file name from Cygwin syntax to
+ native Windows syntax, like 'cygpath -w' does.
+ Returns a freshly allocated file name.
+ On the other platforms, it returns a freshly allocated copy of the
+ argument file name. */
+extern char *cygpath_w (const char *filename);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _CYGPATH_H */