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+# File Name Glob Patterns
+
+A [glob pattern][glob] is a text expression that matches one or more
+file names using wildcards familiar to most users of a command line.
+For example, `*` is a glob that matches any name at all, and
+`Readme.txt` is a glob that matches exactly one file. For purposes of
+Fossil's globs, a complete path name is just a string,
+and the globs do not apply any special meaning to the directory part
+of the name. Thus, the glob `*` matches any name, including any
+directory prefix, and `*/*` matches a name with _one or more_
+directory components.
+
+A glob should not be confused with a [regular expression][regexp] (RE)
+even though they use some of the same special characters for similar
+purposes. [They are not fully compatible][greinc] pattern
+matching languages. Fossil uses globs when matching file names with the
+settings described in this document, not REs.
+
+[glob]:   https://en.wikipedia.org/wiki/Glob_(programming)
+[greinc]: https://unix.stackexchange.com/a/57958/138
+[regexp]: https://en.wikipedia.org/wiki/Regular_expression
+
+[Fossil’s `*-glob` settings](#settings) hold one or more patterns to cause Fossil to
+give matching named files special treatment.  Glob patterns are also
+accepted in options to certain commands and as query parameters to
+certain Fossil UI web pages. For consistency, settings such as
+`empty-dirs` are parsed as a glob even though they aren’t then *applied*
+as a glob since it allows [the same syntax rules](#syntax) to apply.
+
+Where Fossil also accepts globs in commands, this handling may interact
+with your OS’s command shell or its C runtime system, because they may
+have their own glob pattern handling. We will detail such interactions
+below.
+
+
+## <a id="syntax"></a>Syntax
+
+Where Fossil accepts glob patterns, it will usually accept a *list* of
+individual patterns separated from the others by whitespace or commas.
+
+The parser allows whitespace and commas in a pattern by quoting _the
+entire pattern_ with either single or double quotation marks. Internal
+quotation marks are treated literally. Moreover, a pattern that begins
+with a quote mark ends when the first instance of the same mark occurs,
+_not_ at a whitespace or comma. Thus, this:
+
+    "foo bar"qux
+
+…constitutes _two_ patterns rather than one with an embedded space, in
+contravention of normal shell quoting rules.
+
+A list matches a file when any pattern in that list matches.
+
+A pattern must consume and
+match the *entire* file name to succeed. Partial matches are failed matches.
+
+Most characters in a glob pattern consume a single character of the file
+name and must match it exactly. For instance, “a” in a glob simply
+matches the letter “a” in the file name unless it is inside a special
+character sequence.
+
+Other characters have special meaning, and they may include otherwise
+normal characters to give them special meaning:
+
+:Pattern |:Effect
+---------------------------------------------------------------------
+`*`      | Matches any sequence of zero or more characters
+`?`      | Matches exactly one character
+`[...]`  | Matches one character from the enclosed list of characters
+`[^...]` | Matches one character *not* in the enclosed list
+
+Note that unlike [POSIX globs][pg], these special characters and
+sequences are allowed to match `/` directory separators as well as the
+initial `.` in the name of a hidden file or directory. This is because
+Fossil file names are stored as complete path names. The distinction
+between file name and directory name is “underneath” Fossil in this sense.
+
+[pg]: https://pubs.opengroup.org/onlinepubs/9699919799/utilities/V3_chap02.html#tag_18_13
+
+The bracket expressions above require some additional explanation:
+
+ *  A range of characters may be specified with `-`, so `[a-f]` matches
+    exactly the same characters as `[abcdef]`. Ranges reflect Unicode
+    code points without any locale-specific collation sequence.
+    Therefore, this particular sequence never matches the Unicode
+    pre-composed character `é`, for example. (U+00E9)
+
+ *  This dependence on character/code point ordering may have other
+    effects to surprise you. For example, the glob `[A-z]` not only
+    matches upper and lowercase ASCII letters, it also matches several
+    punctuation characters placed between `Z` and `a` in both ASCII and
+    Unicode: `[`, `\`, `]`, `^`, `_`, and <tt>\`</tt>.
+
+ *  You may include a literal `-` in a list by placing it last, just
+    before the `]`.
+
+ *  You may include a literal `]` in a list by making the first
+    character after the `[` or `[^`. At any other place, `]` ends the list.
+
+ *  You may include a literal `^` in a list by placing it anywhere
+    except after the opening `[`.
+
+ *  Beware that a range must be specified from low value to high
+    value: `[z-a]` does not match any character at all, preventing the
+    entire glob from matching.
+
+Some examples of character lists:
+
+:Pattern |:Effect
+---------------------------------------------------------------------
+`[a-d]`  | Matches any one of `a`, `b`, `c`, or `d` but not `ä`
+`[^a-d]` | Matches exactly one character other than `a`, `b`, `c`, or `d`
+`[0-9a-fA-F]` | Matches exactly one hexadecimal digit
+`[a-]`   | Matches either `a` or `-`
+`[][]`   | Matches either `]` or `[`
+`[^]]`   | Matches exactly one character other than `]`
+`[]^]`   | Matches either `]` or `^`
+`[^-]`   | Matches exactly one character other than `-`
+
+White space means the specific ASCII characters TAB, LF, VT, FF, CR,
+and SPACE.  Note that this does not include any of the many additional
+spacing characters available in Unicode such as
+U+00A0, NO-BREAK SPACE.
+
+Because both LF and CR are white space and leading and trailing spaces
+are stripped from each glob in a list, a list of globs may be broken
+into lines between globs when the list is stored in a file, as for a
+versioned setting.
+
+Note that 'single quotes' and "double quotes" are the ASCII straight
+quote characters, not any of the other quotation marks provided in
+Unicode and specifically not the "curly" quotes preferred by
+typesetters and word processors.
+
+
+## File Names to Match
+
+Before it is compared to a glob pattern, each file name is transformed
+to a canonical form:
+
+  *  all directory separators are changed to `/`
+  *  redundant slashes are removed
+  *  all `.` path components are removed
+  *  all `..` path components are resolved
+
+(There are additional details we are ignoring here, but they cover rare
+edge cases and follow the principle of least surprise.)
+
+The glob must match the *entire* canonical file name to be considered a
+match.
+
+The goal is to have a name that is the simplest possible for each
+particular file, and that will be the same regardless of the platform
+you run Fossil on. This is important when you have a repository cloned
+from multiple platforms and have globs in versioned settings: you want
+those settings to be interpreted the same way everywhere.
+
+Beware, however, that all glob matching in Fossil is case sensitive
+regardless of host platform and file system. This will not be a surprise
+on POSIX platforms where file names are usually treated case
+sensitively. However, most Windows file systems are case preserving but
+case insensitive. That is, on Windows, the names `ReadMe` and `README`
+are usually names of the same file. The same is true in other cases,
+such as by default on macOS file systems and in the file system drivers
+for Windows file systems running on non-Windows systems. (e.g. exfat on
+Linux.) Therefore, write your Fossil glob patterns to match the name of
+the file as checked into the repository.
+
+Some example cases:
+
+:Pattern     |:Effect
+--------------------------------------------------------------------------------
+`README`     | Matches only a file named `README` in the root of the tree. It does not match a file named `src/README` because it does not include any characters that consume (and match) the `src/` part.
+`*/README`   | Matches `src/README`. Unlike Unix file globs, it also matches `src/library/README`. However it does not match the file `README` in the root of the tree.
+`*README`    | Matches `src/README` as well as the file `README` in the root of the tree as well as `foo/bar/README` or any other file named `README` in the tree. However, it also matches `A-DIFFERENT-README` and `src/DO-NOT-README`, or any other file whose name ends with `README`.
+`src/README` | Matches `src\README` on Windows because all directory separators are rewritten as `/` in the canonical name before the glob is matched. This makes it much easier to write globs that work on both Unix and Windows.
+`*.[ch]`     | Matches every C source or header file in the tree at the root or at any depth. Again, this is (deliberately) different from Unix file globs and Windows wild cards.
+
+
+## Where Globs are Used
+
+### <a id="settings"></a>Settings that are Globs
+
+These settings are all lists of glob patterns:
+
+:Setting        |:Description
+--------------------------------------------------------------------------------
+`binary-glob`   | Files that should be treated as binary files for committing and merging purposes
+`clean-glob`    | Files that the [`clean`][] command will delete without prompting or allowing undo
+`crlf-glob`     | Files in which it is okay to have `CR`, `CR`+`LF` or mixed line endings.  Set to "`*`" to disable CR+LF checking
+`crnl-glob`     | Alias for the `crlf-glob` setting
+`encoding-glob` | Files that the [`commit`][] command will ignore when issuing warnings about text files that may use another encoding than ASCII or UTF-8.  Set to "`*`" to disable encoding checking
+`ignore-glob`   | Files that the [`add`][], [`addremove`][], [`clean`][], and [`extras`][] commands will ignore
+`keep-glob`     | Files that the [`clean`][] command will keep
+
+All may be [versioned, local, or global](settings.wiki). Use `fossil
+settings` to manage local and global settings, or a file in the
+repository's `.fossil-settings/` folder at the root of the tree named
+for each for versioned setting.
+
+Using versioned settings for these not only has the advantage that
+they are tracked in the repository just like the rest of your project,
+but you can more easily keep longer lists of more complicated glob
+patterns than would be practical in either local or global settings.
+
+The `ignore-glob` is an example of one setting that frequently grows
+to be an elaborate list of files that should be ignored by most
+commands. This is especially true when one (or more) IDEs are used in
+a project because each IDE has its own ideas of how and where to cache
+information that speeds up its browsing and building tasks but which
+need not be preserved in your project's history.
+
+Although the `empty-dirs` setting is not a list of glob patterns as
+such, it is *parsed* that way for consistency among the settings,
+allowing [the list parsing rules above](#syntax) to apply.
+
+
+### <a id="commands"></a>Commands that Refer to Globs
+
+Many of the commands that respect the settings containing globs have
+options to override some or all of the settings. These options are
+usually named to correspond to the setting they override, such as
+`--ignore` to override the `ignore-glob` setting. These commands are:
+
+ *  [`add`][]
+ *  [`addremove`][]
+ *  [`changes`][]
+ *  [`clean`][]
+ *  [`commit`][]
+ *  [`extras`][]
+ *  [`merge`][]
+ *  [`settings`][]
+ *  [`status`][]
+ *  [`touch`][]
+ *  [`unset`][]
+
+The commands [`tarball`][] and [`zip`][] produce compressed archives of a
+specific checkin. They may be further restricted by options that
+specify glob patterns that name files to include or exclude rather
+than archiving the entire checkin.
+
+The commands [`http`][], [`cgi`][], [`server`][], and [`ui`][] that
+implement or support with web servers provide a mechanism to name some
+files to serve with static content where a list of glob patterns
+specifies what content may be served.
+
+[`add`]:       /help/add
+[`addremove`]: /help/addremove
+[`changes`]:   /help/changes
+[`clean`]:     /help/clean
+[`commit`]:    /help/commit
+[`extras`]:    /help/extras
+[`merge`]:     /help/merge
+[`settings`]:  /help/settings
+[`status`]:    /help/status
+[`touch`]:     /help/touch
+[`unset`]:     /help/unset
+
+[`tarball`]:   /help/tarball
+[`zip`]:       /help/zip
+
+[`http`]:      /help/http
+[`cgi`]:       /help/cgi
+[`server`]:    /help/server
+[`ui`]:        /help/ui
+
+
+### Web Pages that Refer to Globs
+
+The [`/timeline`][] page supports the query parameter `chng=GLOBLIST` that
+names a list of glob patterns defining which files to focus the
+timeline on. It also has the query parameters `t=TAG` and `r=TAG` that
+names a tag to focus on, which can be configured with `ms=STYLE` to
+use a glob pattern to match tag names instead of the default exact
+match or a couple of other comparison styles.
+
+The pages [`/tarball`][] and [`/zip`][] generate compressed archives
+of a specific checkin. They may be further restricted by query
+parameters that specify glob patterns that name files to include or
+exclude rather than taking the entire checkin.
+
+[`/timeline`]: /help/www/timeline
+[`/tarball`]:  /help/www/tarball
+[`/zip`]:      /help/www/zip
+
+
+## Platform Quirks
+
+Fossil glob patterns are based on the glob pattern feature of POSIX
+shells. Fossil glob patterns also have a quoting mechanism, discussed
+[above](#syntax). Because other parts of your operating system may interpret glob
+patterns and quotes separately from Fossil, it is often difficult to
+give glob patterns correctly to Fossil on the command line. Quotes and
+special characters in glob patterns are likely to be interpreted when
+given as part of a `fossil` command, causing unexpected behavior.
+
+These problems do not affect [versioned settings files](settings.wiki)
+or Admin &rarr; Settings in Fossil UI. Consequently, it is better to
+set long-term `*-glob` settings via these methods than to use `fossil
+settings` commands.
+
+That advice does not help you when you are giving one-off glob patterns
+in `fossil` commands. The remainder of this section gives remedies and
+workarounds for these problems.
+
+
+### <a id="posix"></a>POSIX Systems
+
+If you are using Fossil on a system with a POSIX-compatible shell
+&mdash; Linux, macOS, the BSDs, Unix, Cygwin, WSL etc. &mdash; the shell
+may expand the glob patterns before passing the result to the `fossil`
+executable.
+
+Sometimes this is exactly what you want.  Consider this command for
+example:
+
+    $ fossil add RE*
+
+If you give that command in a directory containing `README.txt` and
+`RELEASE-NOTES.txt`, the shell will expand the command to:
+
+    $ fossil add README.txt RELEASE-NOTES.txt
+
+…which is compatible with the `fossil add` command's argument list,
+which allows multiple files.
+
+Now consider what happens instead if you say:
+
+    $ fossil add --ignore RE* src/*.c
+
+This *does not* do what you want because the shell will expand both `RE*`
+and `src/*.c`, causing one of the two files matching the `RE*` glob
+pattern to be ignored and the other to be added to the repository. You
+need to say this in that case:
+
+    $ fossil add --ignore 'RE*' src/*.c
+
+The single quotes force a POSIX shell to pass the `RE*` glob pattern
+through to Fossil untouched, which will do its own glob pattern
+matching. There are other methods of quoting a glob pattern or escaping
+its special characters; see your shell's manual.
+
+Beware that Fossil's `--ignore` option does not override explicit file
+mentions:
+
+    $ fossil add --ignore 'REALLY SECRET STUFF.txt' RE*
+
+You might think that would add everything beginning with `RE` *except*
+for `REALLY SECRET STUFF.txt`, but when a file is both given
+explicitly to Fossil and also matches an ignore rule, Fossil asks what
+you want to do with it in the default case; and it does not even ask
+if you gave the `-f` or `--force` option along with `--ignore`.
+
+The spaces in the ignored file name above bring us to another point:
+such file names must be quoted in Fossil glob patterns, lest Fossil
+interpret it as multiple glob patterns, but the shell interprets
+quotation marks itself.
+
+One way to fix both this and the previous problem is:
+
+    $ fossil add --ignore "'REALLY SECRET STUFF.txt'" READ*
+
+The nested quotation marks cause the inner set to be passed through to
+Fossil, and the more specific glob pattern at the end &mdash; that is,
+`READ*` vs `RE*` &mdash; avoids a conflict between explicitly-listed
+files and `--ignore` rules in the `fossil add` command.
+
+Another solution would be to use shell escaping instead of nested
+quoting:
+
+    $ fossil add --ignore "\"REALLY SECRET STUFF.txt\"" READ*
+
+It bears repeating that the two glob patterns here are not interpreted
+the same way when running this command from a *subdirectory* of the top
+checkout directory as when running it at the top of the checkout tree.
+If these files were in a subdirectory of the checkout tree called `doc`
+and that was your current working directory, the command would instead
+have to be:
+
+    $ fossil add --ignore "'doc/REALLY SECRET STUFF.txt'" READ*
+
+The Fossil glob pattern still needs the `doc/` prefix because
+Fossil always interprets glob patterns from the base of the checkout
+directory, not from the current working directory as POSIX shells do.
+
+When in doubt, use `fossil status` after running commands like the
+above to make sure the right set of files were scheduled for insertion
+into the repository before checking the changes in. You never want to
+accidentally check something like a password, an API key, or the
+private half of a public cryptographic key into Fossil repository that
+can be read by people who should not have such secrets.
+
+
+### <a id="windows"></a>Windows
+
+Before we get into Windows-specific details here, beware that this
+section does not apply to the several Microsoft Windows extensions that
+provide POSIX semantics to Windows, for which you want to use the advice
+in [the POSIX section above](#posix) instead:
+
+  *  the ancient and rarely-used [Microsoft POSIX subsystem][mps];
+  *  its now-discontinued replacement feature, [Services for Unix][sfu]; or
+  *  their modern replacement, the [Windows Subsystem for Linux][wsl]
+
+[mps]: https://en.wikipedia.org/wiki/Microsoft_POSIX_subsystem
+[sfu]: https://en.wikipedia.org/wiki/Windows_Services_for_UNIX
+[wsl]: https://en.wikipedia.org/wiki/Windows_Subsystem_for_Linux
+
+(The latter is sometimes incorrectly called "Bash on Windows" or "Ubuntu
+on Windows," but the feature provides much more than just Bash or Ubuntu
+for Windows.)
+
+Neither standard Windows command shell &mdash; `cmd.exe` or PowerShell
+&mdash; expands glob patterns the way POSIX shells do. Windows command
+shells rely on the command itself to do the glob pattern expansion. The
+way this works depends on several factors:
+
+ *  the version of Windows you are using
+ *  which OS upgrades have been applied to it
+ *  the compiler that built your Fossil executable
+ *  whether you are running the command interactively
+ *  whether the command is built against a runtime system that does this
+    at all
+ *  whether the Fossil command is being run from a file named `*.BAT` vs
+    being named `*.CMD`
+
+Usually (but not always!) the C runtime library that your `fossil.exe`
+executable is built against does this glob expansion on Windows so the
+program proper does not have to. This may then interact with the way the
+Windows command shell you’re using handles argument quoting. Because of
+these differences, it is common to find perfectly valid Fossil command
+examples that were written and tested on a POSIX system which then fail
+when tried on Windows.
+
+The most common problem is figuring out how to get a glob pattern passed
+on the command line into `fossil.exe` without it being expanded by the C
+runtime library that your particular Fossil executable is linked to,
+which tries to act like [the POSIX systems described above](#posix). Windows is
+not strongly governed by POSIX, so it has not historically hewed closely
+to its strictures.
+
+For example, consider how you would set `crlf-glob` to `*` in order to
+get normal Windows text files with CR+LF line endings past Fossil's
+"looks like a binary file" check. The na&iuml;ve approach will not work:
+
+    C:\...> fossil setting crlf-glob *
+
+The C runtime library will expand that to the list of all files in the
+current directory, which will probably cause a Fossil error because
+Fossil expects either nothing or option flags after the setting's new
+value, not a list of file names. (To be fair, the same thing will happen
+on POSIX systems, only at the shell level, before `.../bin/fossil` even
+gets run by the shell.)
+
+Let's try again:
+
+    C:\...> fossil setting crlf-glob '*'
+
+Quoting the argument like that will work reliably on POSIX, but it may
+or may not work on Windows. If your Windows command shell interprets the
+quotes, it means `fossil.exe` will see only the bare `*` so the C
+runtime library it is linked to will likely expand the list of files in
+the current directory before the `setting` command gets a chance to
+parse the command line arguments, causing the same failure as above.
+This alternative only works if you’re using a Windows command shell that
+passes the quotes through to the executable *and* you have linked Fossil
+to a C runtime library that interprets the quotes properly itself,
+resulting in a bare `*` getting clear down to Fossil’s `setting` command
+parser.
+
+An approach that *will* work reliably is:
+
+    C:\...> echo * | fossil setting crlf-glob --args -
+
+This works because the built-in Windows command `echo` does not expand its
+arguments, and the `--args -` option makes Fossil read further command
+arguments from its standard input, which is connected to the output
+of `echo` by the pipe. (`-` is a common Unix convention meaning
+"standard input," which Fossil obeys.) A [batch script][fng.cmd] to automate this trick was
+posted on the now-inactive Fossil Mailing List.
+
+[fng.cmd]: https://www.mail-archive.com/fossil-users@lists.fossil-scm.org/msg25099.html
+
+(Ironically, this method will *not* work on POSIX systems because it is
+not up to the command to expand globs. The shell will expand the `*` in
+the `echo` command, so the list of file names will be passed to the
+`fossil` standard input, just as with the first example above!)
+
+Another (usually) correct approach which will work on both Windows and
+POSIX systems:
+
+    C:\...> fossil setting crlf-glob *,
+
+This works because the trailing comma prevents the glob pattern from
+matching any files, unless you happen to have files named with a
+trailing comma in the current directory. If the pattern matches no
+files, it is passed into Fossil's `main()` function as-is by the C
+runtime system. Since Fossil uses commas to separate multiple glob
+patterns, this means "all files from the root of the Fossil checkout
+directory downward and nothing else," which is of course equivalent to
+"all managed files in this repository," our original goal.
+
+
+## Experimenting
+
+To preview the effects of command line glob pattern expansion for
+various glob patterns (unquoted, quoted, comma-terminated), for any
+combination of command shell, OS, C run time, and Fossil version,
+precede the command you want to test with [`test-echo`][] like so:
+
+    $ fossil test-echo setting crlf-glob "*"
+    C:\> echo * | fossil test-echo setting crlf-glob --args -
+
+The [`test-glob`][] command is also handy to test if a string
+matches a glob pattern.
+
+[`test-echo`]: /help/test-echo
+[`test-glob`]: /help/test-glob
+
+
+## Converting `.gitignore` to `ignore-glob`
+
+Many other version control systems handle the specific case of
+ignoring certain files differently from Fossil: they have you create
+individual "ignore" files in each folder, which specify things ignored
+in that folder and below. Usually some form of glob patterns are used
+in those files, but the details differ from Fossil.
+
+In many simple cases, you can just store a top level "ignore" file in
+`.fossil-settings/ignore-glob`. But as usual, there will be lots of
+edge cases.
+
+[Git has a rich collection of ignore files][gitignore] which
+accumulate rules that affect the current command. There are global
+files, per-user files, per workspace unmanaged files, and fully
+version controlled files. Some of the files used have no set name, but
+are called out in configuration files.
+
+[gitignore]: https://git-scm.com/docs/gitignore
+
+In contrast, Fossil has a global setting and a local setting, but the local setting
+overrides the global rather than extending it. Similarly, a Fossil
+command's `--ignore` option replaces the `ignore-glob` setting rather
+than extending it.
+
+With that in mind, translating a `.gitignore` file into
+`.fossil-settings/ignore-glob` may be possible in many cases. Here are
+some of features of `.gitignore` and comments on how they relate to
+Fossil:
+
+ *  "A blank line matches no files...": same in Fossil.
+ *  "A line starting with # serves as a comment...": same in Fossil, including
+    the possibility of escaping an initial `#` with a backslash to allow globs
+    beginning with a hash.
+ *  "Trailing spaces are ignored unless they are quoted..." is similar
+    in Fossil. All whitespace before and after a glob is trimmed in
+    Fossil unless quoted with single or double quotes. Git uses
+    backslash quoting instead, which Fossil does not.
+ *  "An optional prefix "!" which negates the pattern...": not in
+    Fossil.
+ *  Git's globs are relative to the location of the `.gitignore` file:
+    Fossil's globs are relative to the root of the workspace.
+ *  Git's globs and Fossil's globs treat directory separators
+    differently. Git includes a notation for zero or more directories
+    that is not needed in Fossil.
+
+### Example
+
+In a project with source and documentation:
+
+    work
+      +-- doc
+      +-- src
+
+The file `doc/.gitignore` might contain:
+
+    # Finished documents by pandoc via LaTeX
+    *.pdf
+    # Intermediate files
+    *.tex
+    *.toc
+    *.log
+    *.out
+    *.tmp
+
+Entries in `.fossil-settings/ignore-glob` with similar effect, also
+limited to the `doc` folder:
+
+    doc/*.pdf
+    doc/*.tex, doc/*.toc, doc/*.log, doc/*.out, doc/*.tmp
+
+
+
+
+
+## Implementation and References
+
+The implementation of the Fossil-specific glob pattern handling is here:
+
+:File            |:Description
+--------------------------------------------------------------------------------
+[`src/glob.c`][] | pattern list loading, parsing, and generic matching code
+[`src/file.c`][] | application of glob patterns to file names
+
+[`src/glob.c`]: https://fossil-scm.org/home/file/src/glob.c
+[`src/file.c`]: https://fossil-scm.org/home/file/src/file.c
+
+See the [Adding Features to Fossil][aff] document for broader details
+about finding and working with such code.
+
+The actual pattern matching leverages the `GLOB` operator in SQLite, so
+you may find [its documentation][gdoc], [source code][gsrc] and [test
+harness][gtst] helpful.
+
+[aff]:  ./adding_code.wiki
+[gdoc]: https://sqlite.org/lang_expr.html#like
+[gsrc]: https://www.sqlite.org/src/artifact?name=9d52522cc8ae7f5c&ln=570-768
+[gtst]: https://www.sqlite.org/src/artifact?name=66a2c9ac34f74f03&ln=586-673