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ac055d677a
Closes #4370 Explication: In the backtrace in #4370, we see that `buf_write()` was called with non-NULL `fname` and `sfname` arguments, but they've since _become_ NULL. #7 0x00000000004de09d in buf_write (buf=0x1dee040, fname=0x0, fname@entry=0x1e985b0 "/home/sean/src/github.com/snczl/virta/pkg/meld/segment.go", sfname=0x0, sfname@entry=0x1ddfa60 "segment.go", start=1, end=72, eap=eap@entry=0x7ffc6b032e60, append=0, forceit=0, reset_changed=1, filtering=0) at /home/travis/build/neovim/bot-ci/build/neovim/src/nvim/fileio.c:2576 This is most likely due to the code that restores those values from `buf`, which happens just before the fatal call to `os_fileinfo` ```c /* * The autocommands may have changed the name of the buffer, which may * be kept in fname, ffname and sfname. */ if (buf_ffname) ffname = buf->b_ffname; if (buf_sfname) sfname = buf->b_sfname; if (buf_fname_f) fname = buf->b_ffname; if (buf_fname_s) fname = buf->b_sfname; ``` It's worth noting that at this point `ffname` is still non-NULL, so it _could_ be used. However, our current code is purely more strict than Vim in this area, which has caused us problems before (e.g., `getdigits()`). The commentary for `struct file_buffer` clearly indicate that all of `b_ffname`, `b_sfname`, and `b_fname` may be NULL: ```c /* * b_ffname has the full path of the file (NULL for no name). * b_sfname is the name as the user typed it (or NULL). * b_fname is the same as b_sfname, unless ":cd" has been done, * then it is the same as b_ffname (NULL for no name). */ char_u *b_ffname; /* full path file name */ char_u *b_sfname; /* short file name */ char_u *b_fname; /* current file name */ ``` Vim directly calls `stat(2)` which, although it is annotated to tell the compiler that the path argument is non-NULL, does handle a NULL pointer by returning a `-1` value and setting `errno` to `EFAULT`. This satisfies Vim's check, since it treats any `-1` return from `stat(2)` to mean the file doesn't exist (at least in this code path). Note that Vim's mch_stat() implementations on win32 and solaris clearly cannot accept NULL `name`. But the codepaths that call mch_stat will NULL `name` tend to be unix-only (eg: u_read_undo)! |
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| .. | ||
| api | ||
| eval | ||
| fixtures | ||
| os | ||
| buffer_spec.lua | ||
| fileio_spec.lua | ||
| formatc.lua | ||
| garray_spec.lua | ||
| helpers.lua | ||
| mbyte_spec.lua | ||
| memory_spec.lua | ||
| message_spec.lua | ||
| multiqueue_spec.lua | ||
| option_spec.lua | ||
| path_spec.lua | ||
| preload.lua | ||
| preprocess.lua | ||
| profile_spec.lua | ||
| rbuffer_spec.lua | ||
| set.lua | ||
| strings_spec.lua | ||
| tempfile_spec.lua | ||
| testtest_spec.lua | ||