Mercurial > hg > octave-lyh > gnulib-hg
changeset 15813:c8a01782d9d8
relocatable-lib[-lgpl]: Avoid expensive /proc access on Linux, Cygwin.
* lib/relocatable.c (ENABLE_COSTLY_RELOCATABLE): New macro.
(compute_curr_prefix, shared_library_fullname,
find_shared_library_fullname, get_shared_library_fullname, relocate):
Use it together with PIC && INSTALLDIR.
Reported by <jojelino@gmail.com>
via Charles Wilson <cygwin@cwilson.fastmail.fm>.
author | Bruno Haible <bruno@clisp.org> |
---|---|
date | Mon, 03 Oct 2011 13:15:34 +0200 |
parents | d09cc85a3d54 |
children | 625d9f3201d8 |
files | ChangeLog lib/relocatable.c |
diffstat | 2 files changed, 29 insertions(+), 4 deletions(-) [+] |
line wrap: on
line diff
--- a/ChangeLog +++ b/ChangeLog @@ -1,3 +1,13 @@ +2011-10-03 Bruno Haible <bruno@clisp.org> + + relocatable-lib[-lgpl]: Avoid expensive /proc access on Linux, Cygwin. + * lib/relocatable.c (ENABLE_COSTLY_RELOCATABLE): New macro. + (compute_curr_prefix, shared_library_fullname, + find_shared_library_fullname, get_shared_library_fullname, relocate): + Use it together with PIC && INSTALLDIR. + Reported by <jojelino@gmail.com> + via Charles Wilson <cygwin@cwilson.fastmail.fm>. + 2011-10-01 Jim Meyering <meyering@redhat.com> maint.mk: adjust a release-related rule not to require use of gzip
--- a/lib/relocatable.c +++ b/lib/relocatable.c @@ -85,6 +85,19 @@ # define FILE_SYSTEM_PREFIX_LEN(P) 0 #endif +/* Whether to enable the more costly support for relocatable libraries. + It allows libraries to be have been installed with a different original + prefix than the program. But it is quite costly, especially on Cygwin + platforms, see below. Therefore we enable it by default only on native + Win32 platforms. */ +#ifndef ENABLE_COSTLY_RELOCATABLE +# if (defined _WIN32 || defined __WIN32__) && !defined __CYGWIN__ +# define ENABLE_COSTLY_RELOCATABLE 1 +# else +# define ENABLE_COSTLY_RELOCATABLE 0 +# endif +#endif + /* Original installation prefix. */ static char *orig_prefix; static size_t orig_prefix_len; @@ -154,7 +167,7 @@ #endif } -#if !defined IN_LIBRARY || (defined PIC && defined INSTALLDIR) +#if !defined IN_LIBRARY || (defined PIC && defined INSTALLDIR && ENABLE_COSTLY_RELOCATABLE) /* Convenience function: Computes the current installation prefix, based on the original @@ -284,7 +297,7 @@ #endif /* !IN_LIBRARY || PIC */ -#if defined PIC && defined INSTALLDIR +#if defined PIC && defined INSTALLDIR && ENABLE_COSTLY_RELOCATABLE /* Full pathname of shared library, or NULL. */ static char *shared_library_fullname; @@ -330,7 +343,9 @@ #if (defined __linux__ && (__GLIBC__ >= 2 || defined __UCLIBC__)) || defined __CYGWIN__ /* Linux has /proc/self/maps. glibc 2 and uClibc have the getline() function. - Cygwin >= 1.5 has /proc/self/maps and the getline() function too. */ + Cygwin >= 1.5 has /proc/self/maps and the getline() function too. + But it is costly: ca. 0.3 ms on Linux, 3 ms on Cygwin 1.5, and 5 ms on + Cygwin 1.7. */ FILE *fp; /* Open the current process' maps file. It describes one VMA per line. */ @@ -403,7 +418,7 @@ const char * relocate (const char *pathname) { -#if defined PIC && defined INSTALLDIR +#if defined PIC && defined INSTALLDIR && ENABLE_COSTLY_RELOCATABLE static int initialized; /* Initialization code for a shared library. */