From 63fb8f9aa9d19f85599afe4b849b567aefd70a36 Mon Sep 17 00:00:00 2001 From: Zack Weinberg Date: Mon, 5 Feb 2018 14:13:41 -0500 Subject: Post-cleanup 2: minimize _G_config.h. Nearly everything in _G_config.h is either junk or more appropriately defined elsewhere: * _G_fpos_t, _G_fpos64_t, and _G_BUFSIZ are already completely unused. * All remaining uses of _G_va_list have been changed to __gnuc_va_list. * The definition of _G_HAVE_ST_BLKSIZE/_IO_HAVE_ST_BLKSIZE has been inlined into its sole use. * The complete definition of _G_iconv_t has been moved to libio.h and renamed _IO_iconv_t (all actual users used that name). * _G_IO_IO_FILE_VERSION is vestigial; some code cares whether _IO_stdin_used exists, but nothing looks at its value. I've preserved the value as a hardwired constant in csu/init.c. This means csu/init.c no longer needs to include anything. * Many of the headers included by _G_config.h were already being included directly by either either libio.h or stdio.h; the remaining ones were moved to libio.h. * _G_HAVE_MREMAP is still relevant, because mremap genuinely is a Linux extension; it's not in POSIX and as far as I can tell it's not available on the Hurd either. I also preserved _G_HAVE_MMAP, since it's conceivable someone would want to port glibc to a MMU-less, mmap-less environment in the future. Both are now always defined to 1/0 as is the current convention, instead of the older 1/undef convention. These are the only symbols still defined in _G_config.h. * The actual inclusion of _G_config.h moves from libio.h to libioP.h, as this is where a potential override of _G_HAVE_MMAP happens. * The #ifdef logic in libioP.h controlling _IO_JUMPS_OFFSET has been simplified. After this patch, the only surviving _G_ symbols are the struct tag names _G_fpos_t and _G_fpos64_t, which are preserved for the sake of C++ mangled names in applications, and _G_HAVE_MMAP and _G_HAVE_MREMAP, which do not seem worth renaming. Installed stripped libraries are unchanged by this patch. * bits/_G_config.h: Move back to sysdeps/generic/_G_config.h. Delete all contents except for definitions of _G_HAVE_MMAP and _G_HAVE_MREMAP. Add commentary explaining those two symbols. * sysdeps/unix/sysv/linux/bits/_G_config.h: Move back to sysdeps/unix/sysv/linux/_G_config.h. Make same content change as above. * libio/libio.h: Don't include bits/_G_config.h here. Include stddef.h with __need_wchar_t defined. Include bits/types/__mbstate_t.h, bits/types/wint_t.h, and gconv.h. Define _IO_iconv_t here, directly. Don't define _IO_HAVE_ST_BLKSIZE. * libio/libioP.h: Include _G_config.h here. Move include of shlib-compat.h up with rest of includes. Simplify conditionals controlling definition of _IO_JUMPS_OFFSET. * csu/init.c: Remove always-true #if around entire file. Don't include stdio.h. Set _IO_stdin_used to hardwired constant 0x20001, and update commentary. * include/stdio.h, sysdeps/ieee754/ldbl-opt/nldbl-compat.h: Replace all uses of _G_va_list with __gnuc_va_list. * libio/filedoalloc.c: Use #if defined _STATBUF_ST_BLKSIZE instead of #if _IO_HAVE_ST_BLKSIZE. * libio/fileops.c: Test _G_HAVE_MREMAP with #if, not #ifdef. * libio/iofdopen.c, libio/iofopen.c: Test _G_HAVE_MMAP with #if, not #ifdef. --- sysdeps/generic/_G_config.h | 15 +++++++++++++++ 1 file changed, 15 insertions(+) create mode 100644 sysdeps/generic/_G_config.h (limited to 'sysdeps/generic') diff --git a/sysdeps/generic/_G_config.h b/sysdeps/generic/_G_config.h new file mode 100644 index 0000000000..7c917bf64c --- /dev/null +++ b/sysdeps/generic/_G_config.h @@ -0,0 +1,15 @@ +/* Configuration parameters for stdio - generic version. */ + +#ifndef __G_CONFIG_H +#define __G_CONFIG_H 1 + +/* Define to 1 if the operating system supports mmap, 0 otherwise. + This function is required by POSIX but might still be unavailable, + for instance when the hardware lacks support for virtual memory. */ +#define _G_HAVE_MMAP 1 + +/* Define to 1 if the operating system supports mremap, 0 otherwise. + This function is currently a Linux-specific extension. */ +#define _G_HAVE_MREMAP 0 + +#endif /* _G_config.h */ -- cgit 1.4.1