[PATCH] Move 'is_regular_file' from common-utils.c to filestuff.c

Sergio Durigan Junior
2018-09-12T17:31:28Z

There is no reason for 'is_regular_file' to be in common-utils.c; it
belongs to 'filestuff.c'. This commit moves the function definition
and its prototype to the appropriate files.

The motivation behind this move is a failure that happens on certain
cross-compilation environments when compiling the IPA library, due to
the way gnulib probes the need for a 'stat' call replacement. Because
configure checks when cross-compiling are more limited, gnulib decides
that it needs to substitute the 'stat' calls its own 'rpl_stat';
however, the IPA library doesn't link with gnulib, which leads to an
error when compiling 'common-utils.c':

...
/opt/x86-core2--musl--bleeding-edge-2018.09-1/bin/i686-buildroot-linux-musl-g++ -shared -fPIC -Wl,--soname=libinproctrace.so -Wl,--no-undefined -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Os -I. -I. -I./../common -I./../regformats -I./.. -I./../../include -I./../gnulib/import -Ibuild-gnulib-gdbserver/import -D_LARGEFILE_SOURCE -D_LARGEFILE64_SOURCE -D_FILE_OFFSET_BITS=64 -Wall -Wpointer-arith -Wno-unused -Wunused-value -Wunused-function -Wno-switch -Wno-char-subscripts -Wempty-body -Wunused-but-set-parameter -Wunused-but-set-variable -Wno-sign-compare -Wno-narrowing -Wno-error=maybe-uninitialized -DGDBSERVER \
-Wl,--dynamic-list=./proc-service.list -o libinproctrace.so ax-ipa.o common-utils-ipa.o errors-ipa.o format-ipa.o print-utils-ipa.o regcache-ipa.o remote-utils-ipa.o rsp-low-ipa.o tdesc-ipa.o tracepoint-ipa.o utils-ipa.o vec-ipa.o linux-i386-ipa.o linux-x86-tdesc-ipa.o arch/i386-ipa.o -ldl -pthread
/opt/x86-core2--musl--bleeding-edge-2018.09-1/lib/gcc/i686-buildroot-linux-musl/8.2.0/../../../../i686-buildroot-linux-musl/bin/ld: common-utils-ipa.o: in function `is_regular_file(char const*, int*)':
common-utils.c:(.text+0x695): undefined reference to `rpl_stat'
collect2: error: ld returned 1 exit status
Makefile:413: recipe for target 'libinproctrace.so' failed
make[1]: *** [libinproctrace.so] Error 1
...

More details can also be found at:

https://sourceware.org/ml/gdb-patches/2018-09/msg00304.html

The most simple fix for this problem is to move 'is_regular_file' to
'filestuff.c', which is not used by IPA. This ends up making the
files more logically organized as well, since 'is_regular_file' is a
file operation.

No regressions found.

gdb/ChangeLog:
2018-09-12 Sergio Durigan Junior <sergiodj@redhat.com>

* common/common-utils.c: Don't include '<sys/stat.h>'.
(is_regular_file): Move to...
* common/filestuff.c (is_regular_file): ... here.
* common/common-utils.h (is_regular_file): Move to...
* common/filestuff.h (is_regular_file): ... here.
---
gdb/common/common-utils.c | 32 --------------------------------
gdb/common/common-utils.h | 5 -----
gdb/common/filestuff.c | 31 +++++++++++++++++++++++++++++++
gdb/common/filestuff.h | 5 +++++
4 files changed, 36 insertions(+), 37 deletions(-)

diff --git a/gdb/common/common-utils.c b/gdb/common/common-utils.c
index 8d839d10fa..24b3936f3d 100644
--- a/gdb/common/common-utils.c
+++ b/gdb/common/common-utils.c
@@ -20,7 +20,6 @@
#include "common-defs.h"
#include "common-utils.h"
#include "host-defs.h"
-#include <sys/stat.h>
#include <ctype.h>

/* The xmalloc() (libiberty.h) family of memory management routines.
@@ -412,37 +411,6 @@ stringify_argv (const std::vector<char *> &args)

/* See common/common-utils.h. */

-bool
-is_regular_file (const char *name, int *errno_ptr)
-{
- struct stat st;
- const int status = stat (name, &st);
-
- /* Stat should never fail except when the file does not exist.
- If stat fails, analyze the source of error and return true
- unless the file does not exist, to avoid returning false results
- on obscure systems where stat does not work as expected. */
-
- if (status != 0)
- {
- if (errno != ENOENT)
- return true;
- *errno_ptr = ENOENT;
- return false;
- }
-
- if (S_ISREG (st.st_mode))
- return true;
-
- if (S_ISDIR (st.st_mode))
- *errno_ptr = EISDIR;
- else
- *errno_ptr = EINVAL;
- return false;
-}
-
-/* See common/common-utils.h. */
-
ULONGEST
align_up (ULONGEST v, int n)
{
diff --git a/gdb/common/common-utils.h b/gdb/common/common-utils.h
index 7bc6e90f05..a961514fd6 100644
--- a/gdb/common/common-utils.h
+++ b/gdb/common/common-utils.h
@@ -146,11 +146,6 @@ in_inclusive_range (T value, T low, T high)
return value >= low && value <= high;
}

-/* Return true if the file NAME exists and is a regular file.
- If the result is false then *ERRNO_PTR is set to a useful value assuming
- we're expecting a regular file. */
-extern bool is_regular_file (const char *name, int *errno_ptr);
-
/* Ensure that V is aligned to an N byte boundary (B's assumed to be a
power of 2). Round up/down when necessary. Examples of correct
use include:
diff --git a/gdb/common/filestuff.c b/gdb/common/filestuff.c
index f5a754ffa6..fa10165a7c 100644
--- a/gdb/common/filestuff.c
+++ b/gdb/common/filestuff.c
@@ -417,3 +417,34 @@ make_cleanup_close (int fd)
*saved_fd = fd;
return make_cleanup_dtor (do_close_cleanup, saved_fd, xfree);
}
+
+/* See common/filestuff.h. */
+
+bool
+is_regular_file (const char *name, int *errno_ptr)
+{
+ struct stat st;
+ const int status = stat (name, &st);
+
+ /* Stat should never fail except when the file does not exist.
+ If stat fails, analyze the source of error and return true
+ unless the file does not exist, to avoid returning false results
+ on obscure systems where stat does not work as expected. */
+
+ if (status != 0)
+ {
+ if (errno != ENOENT)
+ return true;
+ *errno_ptr = ENOENT;
+ return false;
+ }
+
+ if (S_ISREG (st.st_mode))
+ return true;
+
+ if (S_ISDIR (st.st_mode))
+ *errno_ptr = EISDIR;
+ else
+ *errno_ptr = EINVAL;
+ return false;
+}
diff --git a/gdb/common/filestuff.h b/gdb/common/filestuff.h
index 1a09c729f6..e9328f5358 100644
--- a/gdb/common/filestuff.h
+++ b/gdb/common/filestuff.h
@@ -117,4 +117,9 @@ struct gdb_dir_deleter

typedef std::unique_ptr<DIR, gdb_dir_deleter> gdb_dir_up;

+/* Return true if the file NAME exists and is a regular file.
+ If the result is false then *ERRNO_PTR is set to a useful value assuming
+ we're expecting a regular file. */
+extern bool is_regular_file (const char *name, int *errno_ptr);
+
#endif /* FILESTUFF_H */
--
2.17.1