[newlib-cygwin] FTW Port for Newlib

[newlib-cygwin] FTW Port for Newlib

[Corinna Vinschen]

https://sourceware.org/git/gitweb.cgi?p=newlib-cygwin.git;h=d8ee634506424ce8b3bea057b84ec82dfdd7a821

commit d8ee634506424ce8b3bea057b84ec82dfdd7a821
Author: Eshan dhawan <eshandhawan51@gmail.com>
Date:   Thu Jan 21 03:44:27 2021 +0530

    FTW Port for Newlib
    
    Signed-off-by: Eshan Dhawan <eshandhawan51@gmail.com>

Diff:
---
 newlib/libc/include/ftw.h     |  66 ++++++++++++++++++
 newlib/libc/posix/Makefile.am |   2 +-
 newlib/libc/posix/ftw.c       |  33 +++++++++
 newlib/libc/posix/nftw.c      | 154 ++++++++++++++++++++++++++++++++++++++++++
 4 files changed, 254 insertions(+), 1 deletion(-)

diff --git a/newlib/libc/include/ftw.h b/newlib/libc/include/ftw.h
new file mode 100644
index 000000000..8de1e1e5c
--- /dev/null
+++ b/newlib/libc/include/ftw.h
@@ -0,0 +1,66 @@
+/*
+* Copyright © 2005-2020 Rich Felker, et al.
+*
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files (the
+* "Software"), to deal in the Software without restriction, including
+* without limitation the rights to use, copy, modify, merge, publish,
+* distribute, sublicense, and/or sell copies of the Software, and to
+* permit persons to whom the Software is furnished to do so, subject to
+* the following conditions:
+*
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+#ifndef _FTW_H
+#define	_FTW_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include <sys/features.h>
+#include <sys/stat.h>
+
+/*
+ * Valid flags for the 3rd argument to the function that is passed as the
+ * second argument to ftw(3) and nftw(3).  Say it three times fast!
+ */
+#define	FTW_F		0	/* File.  */
+#define	FTW_D		1	/* Directory.  */
+#define	FTW_DNR		2	/* Directory without read permission.  */
+#define	FTW_DP		3	/* Directory with subdirectories visited.  */
+#define	FTW_NS		4	/* Unknown type; stat() failed.  */
+#define	FTW_SL		5	/* Symbolic link.  */
+#define	FTW_SLN		6	/* Sym link that names a nonexistent file.  */
+
+/*
+ * Flags for use as the 4th argument to nftw(3).  These may be ORed together.
+ */
+#define	FTW_PHYS	0x01	/* Physical walk, don't follow sym links.  */
+#define	FTW_MOUNT	0x02	/* The walk does not cross a mount point.  */
+#define	FTW_DEPTH	0x04	/* Subdirs visited before the dir itself. */
+#define	FTW_CHDIR	0x08	/* Change to a directory before reading it. */
+
+struct FTW {
+	int base;
+	int level;
+};
+
+int ftw(const char *, int (*)(const char *, const struct stat *, int), int);
+int nftw(const char *, int (*)(const char *, const struct stat *, int, struct FTW *), int, int);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
diff --git a/newlib/libc/posix/Makefile.am b/newlib/libc/posix/Makefile.am
index 6cdee1df0..5a358f782 100644
--- a/newlib/libc/posix/Makefile.am
+++ b/newlib/libc/posix/Makefile.am
@@ -10,7 +10,7 @@ GENERAL_SOURCES = \
 	opendir.c readdir.c readdir_r.c \
 	regcomp.c regerror.c regexec.c regfree.c \
 	rewinddir.c sleep.c usleep.c \
-	telldir.c
+	telldir.c ftw.c nftw.c
 
 ELIX_2_SOURCES = \
         scandir.c seekdir.c
diff --git a/newlib/libc/posix/ftw.c b/newlib/libc/posix/ftw.c
new file mode 100644
index 000000000..18cfc24cb
--- /dev/null
+++ b/newlib/libc/posix/ftw.c
@@ -0,0 +1,33 @@
+/*
+* Copyright © 2005-2020 Rich Felker, et al.
+*
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files (the
+* "Software"), to deal in the Software without restriction, including
+* without limitation the rights to use, copy, modify, merge, publish,
+* distribute, sublicense, and/or sell copies of the Software, and to
+* permit persons to whom the Software is furnished to do so, subject to
+* the following conditions:
+*
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+#include <ftw.h>
+
+int ftw(const char *path, int (*fn)(const char *, const struct stat *, int), int fd_limit)
+{
+	/* The following cast assumes that calling a function with one
+	 * argument more than it needs behaves as expected. This is
+	 * actually undefined, but works on all real-world machines. */
+	return nftw(path, (int (*)())fn, fd_limit, FTW_PHYS);
+}
+
diff --git a/newlib/libc/posix/nftw.c b/newlib/libc/posix/nftw.c
new file mode 100644
index 000000000..f4f55f341
--- /dev/null
+++ b/newlib/libc/posix/nftw.c
@@ -0,0 +1,154 @@
+/*
+* Copyright © 2005-2020 Rich Felker, et al.
+*
+* Permission is hereby granted, free of charge, to any person obtaining
+* a copy of this software and associated documentation files (the
+* "Software"), to deal in the Software without restriction, including
+* without limitation the rights to use, copy, modify, merge, publish,
+* distribute, sublicense, and/or sell copies of the Software, and to
+* permit persons to whom the Software is furnished to do so, subject to
+* the following conditions:
+*
+* The above copyright notice and this permission notice shall be
+* included in all copies or substantial portions of the Software.
+*
+* THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+* EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+* MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.
+* IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY
+* CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION OF CONTRACT,
+* TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION WITH THE
+* SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+*/
+
+#include <ftw.h>
+#include <dirent.h>
+#include <sys/stat.h>
+#include <errno.h>
+#include <unistd.h>
+#include <string.h>
+#include <limits.h>
+#include <pthread.h>
+
+struct history
+{
+	struct history *chain;
+	dev_t dev;
+	ino_t ino;
+	int level;
+	int base;
+};
+
+#undef dirfd
+#define dirfd(d) (*(int *)d)
+
+static int do_nftw(char *path, int (*fn)(const char *, const struct stat *, int, struct FTW *), int fd_limit, int flags, struct history *h)
+{
+	size_t l = strlen(path), j = l && path[l-1]=='/' ? l-1 : l;
+	struct stat st;
+	struct history new;
+	int type;
+	int r;
+	struct FTW lev;
+
+	if ((flags & FTW_PHYS) ? lstat(path, &st) : stat(path, &st) < 0) {
+		if (!(flags & FTW_PHYS) && errno==ENOENT && !lstat(path, &st))
+			type = FTW_SLN;
+		else if (errno != EACCES) return -1;
+		else type = FTW_NS;
+	} else if (S_ISDIR(st.st_mode)) {
+		if (access(path, R_OK) < 0) type = FTW_DNR;
+		else if (flags & FTW_DEPTH) type = FTW_DP;
+		else type = FTW_D;
+	} else if (S_ISLNK(st.st_mode)) {
+		if (flags & FTW_PHYS) type = FTW_SL;
+		else type = FTW_SLN;
+	} else {
+		type = FTW_F;
+	}
+
+	if ((flags & FTW_MOUNT) && h && st.st_dev != h->dev)
+		return 0;
+	
+	new.chain = h;
+	new.dev = st.st_dev;
+	new.ino = st.st_ino;
+	new.level = h ? h->level+1 : 0;
+	new.base = j+1;
+	
+	lev.level = new.level;
+	if (h) {
+		lev.base = h->base;
+	} else {
+		size_t k;
+		for (k=j; k && path[k]=='/'; k--);
+		for (; k && path[k-1]!='/'; k--);
+		lev.base = k;
+	}
+
+	if (!(flags & FTW_DEPTH) && (r=fn(path, &st, type, &lev)))
+		return r;
+
+	for (; h; h = h->chain)
+		if (h->dev == st.st_dev && h->ino == st.st_ino)
+			return 0;
+
+	if ((type == FTW_D || type == FTW_DP) && fd_limit) {
+		DIR *d = opendir(path);
+		if (d) {
+			struct dirent *de;
+			while ((de = readdir(d))) {
+				if (de->d_name[0] == '.'
+				 && (!de->d_name[1]
+				  || (de->d_name[1]=='.'
+				   && !de->d_name[2]))) continue;
+				if (strlen(de->d_name) >= PATH_MAX-l) {
+					errno = ENAMETOOLONG;
+					closedir(d);
+					return -1;
+				}
+				path[j]='/';
+				strcpy(path+j+1, de->d_name);
+				if ((r=do_nftw(path, fn, fd_limit-1, flags, &new))) {
+					closedir(d);
+					return r;
+				}
+			}
+			closedir(d);
+		} else if (errno != EACCES) {
+			return -1;
+		}
+	}
+
+	path[l] = 0;
+	if ((flags & FTW_DEPTH) && (r=fn(path, &st, type, &lev)))
+		return r;
+
+	return 0;
+}
+
+int nftw(const char *path, int (*fn)(const char *, const struct stat *, int, struct FTW *), int fd_limit, int flags)
+{
+	int r, cs;
+	size_t l;
+	char pathbuf[PATH_MAX+1];
+
+	if (fd_limit <= 0) return 0;
+
+	l = strlen(path);
+	if (l > PATH_MAX) {
+		errno = ENAMETOOLONG;
+		return -1;
+	}
+	memcpy(pathbuf, path, l+1);
+	
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
+	pthread_setcancelstate(PTHREAD_CANCEL_DISABLE, &cs);
+#endif
+	r = do_nftw(pathbuf, fn, fd_limit, flags, NULL);
+#ifdef _STDIO_WITH_THREAD_CANCELLATION_SUPPORT
+	pthread_setcancelstate(cs, 0);
+#endif
+	return r;
+}
+