posix: always seek to EOF when opening a file in append mode
Python 3 already does this, so skip it there.
Consider the program:
#include <stdio.h>
int main() {
FILE *f = fopen("narf", "w");
fprintf(f, "narf\n");
fclose(f);
f = fopen("narf", "a");
printf("%ld\n", ftell(f));
fprintf(f, "troz\n");
printf("%ld\n", ftell(f));
return 0;
}
on macOS, FreeBSD, and Linux with glibc, this program prints
5
10
but on musl libc (Alpine Linux and probably others) this prints
0
10
By my reading of
https://pubs.opengroup.org/onlinepubs/
009695399/functions/fopen.html
this is technically correct, specifically:
> Opening a file with append mode (a as the first character in the
> mode argument) shall cause all subsequent writes to the file to be
> forced to the then current end-of-file, regardless of intervening
> calls to fseek().
in other words, the file position doesn't really matter in append-mode
files, and we can't depend on it being at all meaningful unless we
perform a seek() before tell() after open(..., 'a'). Experimentally
after a .write() we can do a .tell() and it'll always be reasonable,
but I'm unclear from reading the specification if that's a smart thing
to rely on. This matches what we do on Windows and what Python 3 does
for free, so let's just be consistent. Thanks to Yuya for the idea.
#require serve symlink
Tests whether or not hgwebdir properly handles various symlink topologies.
hide outer repo
$ hg init
$ hg init a
$ echo a > a/a
$ hg --cwd a ci -Ama -d'1 0'
adding a
$ mkdir webdir
$ cd webdir
$ hg init b
$ echo b > b/b
$ hg --cwd b ci -Amb -d'2 0'
adding b
$ hg init c
$ echo c > c/c
$ hg --cwd c ci -Amc -d'3 0'
adding c
$ ln -s ../a al
$ ln -s ../webdir circle
$ root=`pwd`
$ cd ..
$ cat > collections.conf <<EOF
> [collections]
> $root=$root
> EOF
$ hg serve -p $HGPORT -d --pid-file=hg.pid --webdir-conf collections.conf \
> -A access-collections.log -E error-collections.log
$ cat hg.pid >> $DAEMON_PIDS
should succeed
$ get-with-headers.py localhost:$HGPORT '?style=raw'
200 Script output follows
/al/
/b/
/c/
$ get-with-headers.py localhost:$HGPORT 'al/file/tip/a?style=raw'
200 Script output follows
a
$ get-with-headers.py localhost:$HGPORT 'b/file/tip/b?style=raw'
200 Script output follows
b
$ get-with-headers.py localhost:$HGPORT 'c/file/tip/c?style=raw'
200 Script output follows
c
should fail
$ get-with-headers.py localhost:$HGPORT 'circle/al/file/tip/a?style=raw'
404 Not Found
error: repository circle/al/file/tip/a not found
[1]
$ get-with-headers.py localhost:$HGPORT 'circle/b/file/tip/a?style=raw'
404 Not Found
error: repository circle/b/file/tip/a not found
[1]
$ get-with-headers.py localhost:$HGPORT 'circle/c/file/tip/a?style=raw'
404 Not Found
error: repository circle/c/file/tip/a not found
[1]
collections errors
$ cat error-collections.log