current/SOURCES/132-glob-Simplify-the-interface-for-the-GLOB_ALTDIRFUNC-.patch

From 5ae82aa4bf45cdaafeb1c25e09897eabff210de9 Mon Sep 17 00:00:00 2001
From: Florian Weimer <fweimer@redhat.com>
Date: Fri, 29 Apr 2016 09:33:07 +0200
Subject: [PATCH] glob: Simplify the interface for the GLOB_ALTDIRFUNC callback gl_readdir

Previously, application code had to set up the d_namlen member if
the target supported it, involving conditional compilation.  After
this change, glob will use the length of the string in d_name instead
of d_namlen to determine the file name length.  All glibc targets
provide the d_type and d_ino members, and setting them as needed for
gl_readdir is straightforward.

Changing the behavior with regards to d_ino is left to a future
cleanup.

(cherry picked from commit 137fe72eca6923a00381a3ca9f0e7672c1f85e3f)
---
 ChangeLog                  |   15 +++++++++++++++
 manual/examples/mkdirent.c |   42 ++++++++++++++++++++++++++++++++++++++++++
 manual/pattern.texi        |   39 ++++++++++++++++++++++++++++++++++++++-
 posix/bug-glob2.c          |    2 +-
 posix/glob.c               |   24 +++---------------------
 posix/tst-gnuglob.c        |    2 +-
 6 files changed, 100 insertions(+), 24 deletions(-)
 create mode 100644 manual/examples/mkdirent.c

#diff --git a/ChangeLog b/ChangeLog
#index ac7f870..cb3db03 100644
#--- a/ChangeLog
#+++ b/ChangeLog
#@@ -1,3 +1,18 @@
#+2016-04-29  Florian Weimer  <fweimer@redhat.com>
#+
#+      glob: Simplify and document the interface for the GLOB_ALTDIRFUNC
#+      callback function gl_readdir.
#+      * posix/glob.c (NAMELEN, CONVERT_D_NAMLEN): Remove.
#+      (CONVERT_DIRENT_DIRENT64): Use strcpy instead of memcpy.
#+      (glob_in_dir): Remove len.  Use strdup instead of malloc and
#+      memcpy to copy the name.
#+      * manual/pattern.texi (Calling Glob): Document requirements for
#+      implementations of the gl_readdir callback function.
#+      * manual/examples/mkdirent.c: New example.
#+      * posix/bug-glob2.c (my_readdir): Set d_ino to 1 unconditionally,
#+      per the manual guidance.
#+      * posix/tst-gnuglob.c (my_readdir): Likewise.
#+
# 2016-04-28  Stefan Liebler  <stli@linux.vnet.ibm.com>
# 
#       [BZ #18508]
diff --git a/manual/examples/mkdirent.c b/manual/examples/mkdirent.c
new file mode 100644
index 0000000..f8400f4
--- /dev/null
+++ b/manual/examples/mkdirent.c
@@ -0,0 +1,42 @@
+/* Example for creating a struct dirent object for use with glob.
+   Copyright (C) 2016 Free Software Foundation, Inc.
+
+   This program 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 2
+   of the License, or (at your option) any later version.
+
+   This program 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, if not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include <dirent.h>
+#include <errno.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+struct dirent *
+mkdirent (const char *name)
+{
+  size_t dirent_size = offsetof (struct dirent, d_name) + 1;
+  size_t name_length = strlen (name);
+  size_t total_size = dirent_size + name_length;
+  if (total_size < dirent_size)
+    {
+      errno = ENOMEM;
+      return NULL;
+    }
+  struct dirent *result = malloc (total_size);
+  if (result == NULL)
+    return NULL;
+  result->d_type = DT_UNKNOWN;
+  result->d_ino = 1;            /* Do not skip this entry.  */
+  memcpy (result->d_name, name, name_length + 1);
+  return result;
+}
diff --git a/manual/pattern.texi b/manual/pattern.texi
index da848c3..4cf26a7 100644
--- a/manual/pattern.texi
+++ b/manual/pattern.texi
@@ -237,7 +237,44 @@ function used to read the contents of a directory.  It is used if the
 @code{GLOB_ALTDIRFUNC} bit is set in the flag parameter.  The type of
 this field is @w{@code{struct dirent *(*) (void *)}}.
 
-This is a GNU extension.
+An implementation of @code{gl_readdir} needs to initialize the following
+members of the @code{struct dirent} object:
+
+@table @code
+@item d_type
+This member should be set to the file type of the entry if it is known.
+Otherwise, the value @code{DT_UNKNOWN} can be used.  The @code{glob}
+function may use the specified file type to avoid callbacks in cases
+where the file type indicates that the data is not required.
+
+@item d_ino
+This member needs to be non-zero, otherwise @code{glob} may skip the
+current entry and call the @code{gl_readdir} callback function again to
+retrieve another entry.
+
+@item d_name
+This member must be set to the name of the entry.  It must be
+null-terminated.
+@end table
+
+The example below shows how to allocate a @code{struct dirent} object
+containing a given name.
+
+@smallexample
+@include mkdirent.c.texi
+@end smallexample
+
+The @code{glob} function reads the @code{struct dirent} members listed
+above and makes a copy of the file name in the @code{d_name} member
+immediately after the @code{gl_readdir} callback function returns.
+Future invocations of any of the callback functions may dealloacte or
+reuse the buffer.  It is the responsibility of the caller of the
+@code{glob} function to allocate and deallocate the buffer, around the
+call to @code{glob} or using the callback functions.  For example, an
+application could allocate the buffer in the @code{gl_readdir} callback
+function, and deallocate it in the @code{gl_closedir} callback function.
+
+The @code{gl_readdir} member is a GNU extension.
 
 @item gl_opendir
 The address of an alternative implementation of the @code{opendir}
diff --git a/posix/bug-glob2.c b/posix/bug-glob2.c
index 8e21deb..1b1ca5a 100644
--- a/posix/bug-glob2.c
+++ b/posix/bug-glob2.c
@@ -193,7 +193,7 @@ my_readdir (void *gdir)
       return NULL;
     }
 
-  dir->d.d_ino = dir->idx;
+  dir->d.d_ino = 1;            /* glob should not skip this entry.  */
 
 #ifdef _DIRENT_HAVE_D_TYPE
   dir->d.d_type = filesystem[dir->idx].type;
diff --git a/posix/glob.c b/posix/glob.c
index f143108..0574913 100644
--- a/posix/glob.c
+++ b/posix/glob.c
@@ -57,10 +57,8 @@
 
 #if defined HAVE_DIRENT_H || defined __GNU_LIBRARY__
 # include <dirent.h>
-# define NAMLEN(dirent) strlen((dirent)->d_name)
 #else
 # define dirent direct
-# define NAMLEN(dirent) (dirent)->d_namlen
 # ifdef HAVE_SYS_NDIR_H
 #  include <sys/ndir.h>
 # endif
@@ -76,12 +74,6 @@
 #endif
 
 
-/* In GNU systems, <dirent.h> defines this macro for us.  */
-#ifdef _D_NAMLEN
-# undef NAMLEN
-# define NAMLEN(d) _D_NAMLEN(d)
-#endif
-
 /* When used in the GNU libc the symbol _DIRENT_HAVE_D_TYPE is available
    if the `d_type' member for `struct dirent' is available.
    HAVE_STRUCT_DIRENT_D_TYPE plays the same role in GNULIB.  */
@@ -105,12 +97,6 @@
 
 /* If the system has the `struct dirent64' type we use it internally.  */
 #if defined _LIBC && !defined COMPILE_GLOB64
-# if defined HAVE_DIRENT_H || defined __GNU_LIBRARY__
-#  define CONVERT_D_NAMLEN(d64, d32)
-# else
-#  define CONVERT_D_NAMLEN(d64, d32) \
-  (d64)->d_namlen = (d32)->d_namlen;
-# endif
 
 # if (defined POSIX || defined WINDOWS32) && !defined __GNU_LIBRARY__
 #  define CONVERT_D_INO(d64, d32)
@@ -127,8 +113,7 @@
 # endif
 
 # define CONVERT_DIRENT_DIRENT64(d64, d32) \
-  memcpy ((d64)->d_name, (d32)->d_name, NAMLEN (d32) + 1);                   \
-  CONVERT_D_NAMLEN (d64, d32)                                                \
+  strcpy ((d64)->d_name, (d32)->d_name);                                     \
   CONVERT_D_INO (d64, d32)                                                   \
   CONVERT_D_TYPE (d64, d32)
 #endif
@@ -1562,7 +1547,6 @@ glob_in_dir (const char *pattern, const char *directory, int flags,
          while (1)
            {
              const char *name;
-             size_t len;
 #if defined _LIBC && !defined COMPILE_GLOB64
              struct dirent64 *d;
              union
@@ -1630,12 +1614,10 @@ glob_in_dir (const char *pattern, const char *directory, int flags,
                          names = newnames;
                          cur = 0;
                        }
-                     len = NAMLEN (d);
-                     names->name[cur] = (char *) malloc (len + 1);
+                     names->name[cur] = strdup (d->d_name);
                      if (names->name[cur] == NULL)
                        goto memory_error;
-                     *((char *) mempcpy (names->name[cur++], name, len))
-                       = '\0';
+                     ++cur;
                      ++nfound;
                    }
                }
diff --git a/posix/tst-gnuglob.c b/posix/tst-gnuglob.c
index 1c72357..48c7527 100644
--- a/posix/tst-gnuglob.c
+++ b/posix/tst-gnuglob.c
@@ -211,7 +211,7 @@ my_readdir (void *gdir)
       return NULL;
     }
 
-  dir->d.d_ino = dir->idx;
+  dir->d.d_ino = 1;            /* glob should not skip this entry.  */
 
 #ifdef _DIRENT_HAVE_D_TYPE
   dir->d.d_type = filesystem[dir->idx].type;
-- 
1.7.1

1	From 5ae82aa4bf45cdaafeb1c25e09897eabff210de9 Mon Sep 17 00:00:00 2001
2	From: Florian Weimer <fweimer@redhat.com>
3	Date: Fri, 29 Apr 2016 09:33:07 +0200
4	Subject: [PATCH] glob: Simplify the interface for the GLOB_ALTDIRFUNC callback gl_readdir
5
6	Previously, application code had to set up the d_namlen member if
7	the target supported it, involving conditional compilation. After
8	this change, glob will use the length of the string in d_name instead
9	of d_namlen to determine the file name length. All glibc targets
10	provide the d_type and d_ino members, and setting them as needed for
11	gl_readdir is straightforward.
12
13	Changing the behavior with regards to d_ino is left to a future
14	cleanup.
15
16	(cherry picked from commit 137fe72eca6923a00381a3ca9f0e7672c1f85e3f)
17	---
18	ChangeLog \| 15 +++++++++++++++
19	manual/examples/mkdirent.c \| 42 ++++++++++++++++++++++++++++++++++++++++++
20	manual/pattern.texi \| 39 ++++++++++++++++++++++++++++++++++++++-
21	posix/bug-glob2.c \| 2 +-
22	posix/glob.c \| 24 +++---------------------
23	posix/tst-gnuglob.c \| 2 +-
24	6 files changed, 100 insertions(+), 24 deletions(-)
25	create mode 100644 manual/examples/mkdirent.c
26
27	#diff --git a/ChangeLog b/ChangeLog
28	#index ac7f870..cb3db03 100644
29	#--- a/ChangeLog
30	#+++ b/ChangeLog
31	#@@ -1,3 +1,18 @@
32	#+2016-04-29 Florian Weimer <fweimer@redhat.com>
33	#+
34	#+ glob: Simplify and document the interface for the GLOB_ALTDIRFUNC
35	#+ callback function gl_readdir.
36	#+ * posix/glob.c (NAMELEN, CONVERT_D_NAMLEN): Remove.
37	#+ (CONVERT_DIRENT_DIRENT64): Use strcpy instead of memcpy.
38	#+ (glob_in_dir): Remove len. Use strdup instead of malloc and
39	#+ memcpy to copy the name.
40	#+ * manual/pattern.texi (Calling Glob): Document requirements for
41	#+ implementations of the gl_readdir callback function.
42	#+ * manual/examples/mkdirent.c: New example.
43	#+ * posix/bug-glob2.c (my_readdir): Set d_ino to 1 unconditionally,
44	#+ per the manual guidance.
45	#+ * posix/tst-gnuglob.c (my_readdir): Likewise.
46	#+
47	# 2016-04-28 Stefan Liebler <stli@linux.vnet.ibm.com>
48	#
49	# [BZ #18508]
50	diff --git a/manual/examples/mkdirent.c b/manual/examples/mkdirent.c
51	new file mode 100644
52	index 0000000..f8400f4
53	--- /dev/null
54	+++ b/manual/examples/mkdirent.c
55	@@ -0,0 +1,42 @@
56	+/* Example for creating a struct dirent object for use with glob.
57	+ Copyright (C) 2016 Free Software Foundation, Inc.
58	+
59	+ This program is free software; you can redistribute it and/or
60	+ modify it under the terms of the GNU General Public License
61	+ as published by the Free Software Foundation; either version 2
62	+ of the License, or (at your option) any later version.
63	+
64	+ This program is distributed in the hope that it will be useful,
65	+ but WITHOUT ANY WARRANTY; without even the implied warranty of
66	+ MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
67	+ GNU General Public License for more details.
68	+
69	+ You should have received a copy of the GNU General Public License
70	+ along with this program; if not, if not, see <http://www.gnu.org/licenses/>.
71	+*/
72	+
73	+#include <dirent.h>
74	+#include <errno.h>
75	+#include <stddef.h>
76	+#include <stdlib.h>
77	+#include <string.h>
78	+
79	+struct dirent *
80	+mkdirent (const char *name)
81	+{
82	+ size_t dirent_size = offsetof (struct dirent, d_name) + 1;
83	+ size_t name_length = strlen (name);
84	+ size_t total_size = dirent_size + name_length;
85	+ if (total_size < dirent_size)
86	+ {
87	+ errno = ENOMEM;
88	+ return NULL;
89	+ }
90	+ struct dirent *result = malloc (total_size);
91	+ if (result == NULL)
92	+ return NULL;
93	+ result->d_type = DT_UNKNOWN;
94	+ result->d_ino = 1; /* Do not skip this entry. */
95	+ memcpy (result->d_name, name, name_length + 1);
96	+ return result;
97	+}
98	diff --git a/manual/pattern.texi b/manual/pattern.texi
99	index da848c3..4cf26a7 100644
100	--- a/manual/pattern.texi
101	+++ b/manual/pattern.texi
102	@@ -237,7 +237,44 @@ function used to read the contents of a directory. It is used if the
103	@code{GLOB_ALTDIRFUNC} bit is set in the flag parameter. The type of
104	this field is @w{@code{struct dirent () (void *)}}.
105
106	-This is a GNU extension.
107	+An implementation of @code{gl_readdir} needs to initialize the following
108	+members of the @code{struct dirent} object:
109	+
110	+@table @code
111	+@item d_type
112	+This member should be set to the file type of the entry if it is known.
113	+Otherwise, the value @code{DT_UNKNOWN} can be used. The @code{glob}
114	+function may use the specified file type to avoid callbacks in cases
115	+where the file type indicates that the data is not required.
116	+
117	+@item d_ino
118	+This member needs to be non-zero, otherwise @code{glob} may skip the
119	+current entry and call the @code{gl_readdir} callback function again to
120	+retrieve another entry.
121	+
122	+@item d_name
123	+This member must be set to the name of the entry. It must be
124	+null-terminated.
125	+@end table
126	+
127	+The example below shows how to allocate a @code{struct dirent} object
128	+containing a given name.
129	+
130	+@smallexample
131	+@include mkdirent.c.texi
132	+@end smallexample
133	+
134	+The @code{glob} function reads the @code{struct dirent} members listed
135	+above and makes a copy of the file name in the @code{d_name} member
136	+immediately after the @code{gl_readdir} callback function returns.
137	+Future invocations of any of the callback functions may dealloacte or
138	+reuse the buffer. It is the responsibility of the caller of the
139	+@code{glob} function to allocate and deallocate the buffer, around the
140	+call to @code{glob} or using the callback functions. For example, an
141	+application could allocate the buffer in the @code{gl_readdir} callback
142	+function, and deallocate it in the @code{gl_closedir} callback function.
143	+
144	+The @code{gl_readdir} member is a GNU extension.
145
146	@item gl_opendir
147	The address of an alternative implementation of the @code{opendir}
148	diff --git a/posix/bug-glob2.c b/posix/bug-glob2.c
149	index 8e21deb..1b1ca5a 100644
150	--- a/posix/bug-glob2.c
151	+++ b/posix/bug-glob2.c
152	@@ -193,7 +193,7 @@ my_readdir (void *gdir)
153	return NULL;
154	}
155
156	- dir->d.d_ino = dir->idx;
157	+ dir->d.d_ino = 1; /* glob should not skip this entry. */
158
159	#ifdef _DIRENT_HAVE_D_TYPE
160	dir->d.d_type = filesystem[dir->idx].type;
161	diff --git a/posix/glob.c b/posix/glob.c
162	index f143108..0574913 100644
163	--- a/posix/glob.c
164	+++ b/posix/glob.c
165	@@ -57,10 +57,8 @@
166
167	#if defined HAVE_DIRENT_H \|\| defined __GNU_LIBRARY__
168	# include <dirent.h>
169	-# define NAMLEN(dirent) strlen((dirent)->d_name)
170	#else
171	# define dirent direct
172	-# define NAMLEN(dirent) (dirent)->d_namlen
173	# ifdef HAVE_SYS_NDIR_H
174	# include <sys/ndir.h>
175	# endif
176	@@ -76,12 +74,6 @@
177	#endif
178
179
180	-/* In GNU systems, <dirent.h> defines this macro for us. */
181	-#ifdef _D_NAMLEN
182	-# undef NAMLEN
183	-# define NAMLEN(d) _D_NAMLEN(d)
184	-#endif
185	-
186	/* When used in the GNU libc the symbol _DIRENT_HAVE_D_TYPE is available
187	if the `d_type' member for `struct dirent' is available.
188	HAVE_STRUCT_DIRENT_D_TYPE plays the same role in GNULIB. */
189	@@ -105,12 +97,6 @@
190
191	/* If the system has the `struct dirent64' type we use it internally. */
192	#if defined _LIBC && !defined COMPILE_GLOB64
193	-# if defined HAVE_DIRENT_H \|\| defined __GNU_LIBRARY__
194	-# define CONVERT_D_NAMLEN(d64, d32)
195	-# else
196	-# define CONVERT_D_NAMLEN(d64, d32) \
197	- (d64)->d_namlen = (d32)->d_namlen;
198	-# endif
199
200	# if (defined POSIX \|\| defined WINDOWS32) && !defined __GNU_LIBRARY__
201	# define CONVERT_D_INO(d64, d32)
202	@@ -127,8 +113,7 @@
203	# endif
204
205	# define CONVERT_DIRENT_DIRENT64(d64, d32) \
206	- memcpy ((d64)->d_name, (d32)->d_name, NAMLEN (d32) + 1); \
207	- CONVERT_D_NAMLEN (d64, d32) \
208	+ strcpy ((d64)->d_name, (d32)->d_name); \
209	CONVERT_D_INO (d64, d32) \
210	CONVERT_D_TYPE (d64, d32)
211	#endif
212	@@ -1562,7 +1547,6 @@ glob_in_dir (const char pattern, const char directory, int flags,
213	while (1)
214	{
215	const char *name;
216	- size_t len;
217	#if defined _LIBC && !defined COMPILE_GLOB64
218	struct dirent64 *d;
219	union
220	@@ -1630,12 +1614,10 @@ glob_in_dir (const char pattern, const char directory, int flags,
221	names = newnames;
222	cur = 0;
223	}
224	- len = NAMLEN (d);
225	- names->name[cur] = (char *) malloc (len + 1);
226	+ names->name[cur] = strdup (d->d_name);
227	if (names->name[cur] == NULL)
228	goto memory_error;
229	- ((char ) mempcpy (names->name[cur++], name, len))
230	- = '\0';
231	+ ++cur;
232	++nfound;
233	}
234	}
235	diff --git a/posix/tst-gnuglob.c b/posix/tst-gnuglob.c
236	index 1c72357..48c7527 100644
237	--- a/posix/tst-gnuglob.c
238	+++ b/posix/tst-gnuglob.c
239	@@ -211,7 +211,7 @@ my_readdir (void *gdir)
240	return NULL;
241	}
242
243	- dir->d.d_ino = dir->idx;
244	+ dir->d.d_ino = 1; /* glob should not skip this entry. */
245
246	#ifdef _DIRENT_HAVE_D_TYPE
247	dir->d.d_type = filesystem[dir->idx].type;
248	--
249	1.7.1
250