In order for these formats to be machine-parseable, characters used as delimiters must be escaped. Linux escapes space, newline, backslash, and hash (because code that parses mounts/mtab and fstab would handle comments) using octal escapes. Replicate that behavior here.
Addresses: https://cygwin.com/pipermail/cygwin/2024-June/256082.html Signed-off-by: Jeremy Drake <cyg...@jdrake.com> --- I took a crack at adding escaping to "mountstuff". It seems like there might be other such /proc entries that are expected to be machine-readable that might need escaping. As such, perhaps the escape_string* functions should be in some other file (and not static) so other source files can call them too. I made some effort to match formatting, but I may well have missed something (I just noticed I missed space between function name and open paren on the new functions, I went ahead and fixed that in the patch manually in the email client). winsup/cygwin/fhandler/process.cc | 81 +++++++++++++++++++++++++++---- 1 file changed, 71 insertions(+), 10 deletions(-) diff --git a/winsup/cygwin/fhandler/process.cc b/winsup/cygwin/fhandler/process.cc index 37bdff84e3..0ab07bd119 100644 --- a/winsup/cygwin/fhandler/process.cc +++ b/winsup/cygwin/fhandler/process.cc @@ -1317,9 +1317,44 @@ extern "C" { struct mntent *getmntent (FILE *); }; +static size_t +escape_string_length (const char *str, const char *escapees) +{ + size_t i, len = 0; + + for (i = strcspn (str, escapees); + str[i]; + i += strcspn (str + i + 1, escapees) + 1) + if ((unsigned char) str[i] < 8) + len += 2; + else if ((unsigned char) str[i] < 64) + len += 3; + else + len += 4; + return len + i; +} + +static size_t +escape_string (char *destbuf, const char *str, const char *escapees) +{ + size_t s, i; + char *p = destbuf; + + for (s = 0, i = strcspn (str, escapees); + str[i]; + s = i + 1, i += strcspn (str + s, escapees) + 1) + { + p = stpncpy (p, str + s, i - s); + p += __small_sprintf (p, "\\0%o", (int)(unsigned char) str[i]); + } + p = stpcpy (p, str + s); + return (p - destbuf); +} + static off_t format_process_mountstuff (void *data, char *&destbuf, bool mountinfo) { + static const char MOUNTSTUFF_ESCAPEES[] = " \n\\#"; _pinfo *p = (_pinfo *) data; user_info *u_shared = NULL; HANDLE u_hdl = NULL; @@ -1369,9 +1404,9 @@ format_process_mountstuff (void *data, char *&destbuf, bool mountinfo) continue; } destbuf = (char *) crealloc_abort (destbuf, len - + strlen (mnt->mnt_fsname) - + strlen (mnt->mnt_dir) - + strlen (mnt->mnt_type) + + escape_string_length (mnt->mnt_fsname, MOUNTSTUFF_ESCAPEES) + + escape_string_length (mnt->mnt_dir, MOUNTSTUFF_ESCAPEES) + + escape_string_length (mnt->mnt_type, MOUNTSTUFF_ESCAPEES) + strlen (mnt->mnt_opts) + 30); if (mountinfo) @@ -1380,18 +1415,44 @@ format_process_mountstuff (void *data, char *&destbuf, bool mountinfo) dev_t dev = pc.exists () ? pc.fs_serial_number () : -1; len += __small_sprintf (destbuf + len, - "%d %d %d:%d / %s %s - %s %s %s\n", + "%d %d %d:%d / ", iteration, iteration, - major (dev), minor (dev), - mnt->mnt_dir, mnt->mnt_opts, - mnt->mnt_type, mnt->mnt_fsname, + major (dev), minor (dev)); + len += escape_string (destbuf + len, + mnt->mnt_dir, + MOUNTSTUFF_ESCAPEES); + len += __small_sprintf (destbuf + len, + " %s - ", + mnt->mnt_opts); + len += escape_string (destbuf + len, + mnt->mnt_type, + MOUNTSTUFF_ESCAPEES); + destbuf[len++] = ' '; + len += escape_string (destbuf + len, + mnt->mnt_fsname, + MOUNTSTUFF_ESCAPEES); + len += __small_sprintf (destbuf + len, + " %s\n", (pc.fs_flags () & FILE_READ_ONLY_VOLUME) ? "ro" : "rw"); } else - len += __small_sprintf (destbuf + len, "%s %s %s %s %d %d\n", - mnt->mnt_fsname, mnt->mnt_dir, mnt->mnt_type, - mnt->mnt_opts, mnt->mnt_freq, mnt->mnt_passno); + { + len += escape_string (destbuf + len, + mnt->mnt_fsname, + MOUNTSTUFF_ESCAPEES); + destbuf[len++] = ' '; + len += escape_string (destbuf + len, + mnt->mnt_dir, + MOUNTSTUFF_ESCAPEES); + destbuf[len++] = ' '; + len += escape_string (destbuf + len, + mnt->mnt_type, + MOUNTSTUFF_ESCAPEES); + len += __small_sprintf (destbuf + len, " %s %d %d\n", + mnt->mnt_opts, mnt->mnt_freq, + mnt->mnt_passno); + } } /* Restore available_drives */ -- 2.45.2.windows.1
