The commit c4d8d937d5 added null byte for
obstack_vprintf and thus to obstack_printf. I probably lost my marbles
but the same test I run previously now won't append null byte at the end
and this "fix" now causes regressions in code using obstack.
For the reference this is the testing code:
#define _GNU_SOURCE
#include <obstack.h>
#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#define obstack_chunk_alloc malloc
#define obstack_chunk_free free
static void print(struct obstack *obs, const char *fmt, ...) {
va_list arg;
va_start(arg, fmt);
obstack_vprintf(obs, fmt, arg);
va_end(arg);
}
int main(int argc, char *argv[]) {
struct obstack obs;
obstack_init(&obs);
obstack_printf(&obs, "this %s", "text ");
obstack_printf(&obs, "is appended");
print(&obs, " as well as %s", "vprintf text");
obstack_1grow(&obs, '\0');
printf("%s\n", (char *)obstack_finish(&obs));
obstack_free(&obs, NULL);
return 0;
}
The output on NuttX without this patch:
> obstest
this text
The output on NuttX with this patch:
> obstest
this text is appended as well as vprintf text
The output with GlibC:
$ gcc test.c && ./a.out
this text is appended as well as vprintf text
$ ldd a.out
linux-vdso.so.1 (0x00007ffff7fc5000)
libc.so.6 => /nix/store/3dyw8dzj9ab4m8hv5dpyx7zii8d0w6fi-glibc-2.39-52/lib/libc.so.6 (0x00007ffff7dc8000)
/nix/store/3dyw8dzj9ab4m8hv5dpyx7zii8d0w6fi-glibc-2.39-52/lib/ld-linux-x86-64.so.2 => /nix/store/3dyw8dzj9ab4m8hv5dpyx7zii8d0w6fi-glibc-2.39-52/lib64/ld-linux-x86-64.so.2 (0x00007ffff7fc7000)
The output with Musl (and obstack_vprintf removed):
$ gcc -lobstack test-musl.c && ./a.out
this text is appended
$ ldd a.out
/nix/store/00w9nz0343pxk7hbsjzq9bzaby65hk4g-musl-1.2.3/lib/ld-musl-x86_64.so.1 (0x7ffff7f4b000)
libobstack.so.1 => /nix/store/qvv16dqn85qwz9vz9wvpnv435z0n5msr-musl-obstack-1.2.3/lib/libobstack.so.1 (0x7ffff7f3b000)
libc.so => /nix/store/00w9nz0343pxk7hbsjzq9bzaby65hk4g-musl-1.2.3/lib/ld-musl-x86_64.so.1 (0x7ffff7f4b000)