From: Mark Jamsek Subject: Re: got rebase or diff library bug To: Mark Jamsek Cc: Christian Weisgerber , gameoftrees@openbsd.org Date: Mon, 05 Aug 2024 22:26:13 +1000 Mark Jamsek wrote: > Christian Weisgerber wrote: > > Christian Weisgerber: > > > > > It also fixes my original problem. I rebased the llvm18 branch in > > > my repository and the GCNRegPressure.cpp file survived unscathed. > > > > Wait, no, it gained a trailing '\n': > > Thanks, naddy! I was worried about that case. > > I'll see if if I can come up with a minimal repro and a proper fix. I've not yet managed to produce a minimal reproduction of your llvm case such that the trailing newline is appended with the previous diff, but I'm pretty sure I know why it's happening: it's because the ed script is not necessarily generated in order so we end up unsetting no_eofnl. If I'm right, the below diff should now work with your llvm merge and it's still working with the simple hello\nworld\n+fubarEOF case. Please let me know if GCNRegPressure.cpp still survives your llvm rebase unscathed and without gaining the trailing '\n', and I'll keep working on a minimal test case for it too. Thanks, naddy! diffstat f997e889eb0517a24a28f2f4000d6915683fef86 de493b727770ab0c07070cc9aff938371f4e4132 M lib/diff3.c | 17+ 0- 1 file changed, 17 insertions(+), 0 deletions(-) diff f997e889eb0517a24a28f2f4000d6915683fef86 de493b727770ab0c07070cc9aff938371f4e4132 commit - f997e889eb0517a24a28f2f4000d6915683fef86 commit + de493b727770ab0c07070cc9aff938371f4e4132 blob - c1ca2fdf44d461cda6adb950263ed6a9775971ac blob + 870a8eac2fb905a8f66de48e38c247aa970d2c5e --- lib/diff3.c +++ lib/diff3.c @@ -155,6 +155,8 @@ struct diff3_state { char *buf; + int no_eofnl; /* set if the merged file has no eof newline */ + BUF *diffbuf; }; @@ -417,6 +419,10 @@ out: err = got_error_from_errno("fclose"); } if (err == NULL && diffb) { + dlen = buf_len(diffb); + if (d3s->no_eofnl && dlen > 0 && + buf_getc(diffb, dlen - 1) == '\n') + --diffb->cb_len; if (buf_write_fd(diffb, outfd) < 0) err = got_error_from_errno("buf_write_fd"); *overlapcnt = d3s->overlapcnt; @@ -1063,6 +1069,17 @@ edscript(int n, struct diff3_state *d3s) } if (!d3s->overlap[n]) { + size_t len; + + len = buf_len(d3s->diffbuf); + if (len > 0) { + if (buf_getc(d3s->diffbuf, len - 1) != '\n') { + err = buf_putc(d3s->diffbuf, '\n'); + if (err != NULL) + goto done; + d3s->no_eofnl = 1; + } + } err = diff_output(d3s->diffbuf, ".\n"); if (err) goto done; -- Mark Jamsek GPG: F2FF 13DE 6A06 C471 CA80 E6E2 2930 DC66 86EE CF68