d/freebsd-nq
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

Place some hooks (__stdin, __stdout, __stderr) into libc for a future

Browse Source 
ABI change.  There is some serious evilness here to work around some
gcc weaknesses.  We need to know the sizeof(FILE) manually until __sF
goes away in the next major bump.  We have the size for Alpha and i386,
missing is ia64, ppc and sparc* (and i386 with 64 bit longs).
At some point down the track we can change the stdin etc #defines to
stop hard coding the size of FILE into application binaries.

Lots of head scratching and ideas and testing by: green, imp
This commit is contained in:
Peter Wemm 2001-02-20 01:56:52 +00:00
parent 47585c927f
commit 3d92fc05aa
1 changed files with 23 additions and 0 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

23
lib/libc/stdio/findfp.c
View File

@ -77,6 +77,26 @@ FILE __sF[3] = {
std(__SWR|__SNBF, STDERR_FILENO)
};
/*
* The following kludge is done to ensure enough binary compatibility
* with future versions of libc. Or rather it allows us to work with
* libraries that have been built with a newer libc that defines these
* symbols and expects libc to provide them. We only have need to support
* i386 and alpha because they are the only "old" systems we have deployed.
*/
#if defined(__i386__)
#define FILE_SIZE 88
#elif defined(__alpha__)
#define FILE_SIZE 152
#endif
#ifndef FILE_SIZE
#error "You must define FILE_SIZE for this platform"
#endif
#define X(loc, sym) __strong_reference(loc, sym)
X(__sF + FILE_SIZE * 0, __stdin);
X(__sF + FILE_SIZE * 1, __stdout);
X(__sF + FILE_SIZE * 2, __stderr);
struct glue __sglue = { &uglue, 3, __sF };
static struct glue *lastglue = &uglue;
@ -213,11 +233,14 @@ _cleanup()
/*
* __sinit() is called whenever stdio's internal variables must be set up.
*/
#define SIZEMSG "WARNING: FILE_SIZE != sizeof(FILE)\n"
void
__sinit()
{
int i;
if (FILE_SIZE != sizeof(FILE))
write(2, SIZEMSG, sizeof(SIZEMSG) - 1);
THREAD_LOCK();
if (__sdidinit == 0) {
/* Set _extra for the usual suspects. */