Commit Graph
5 Commits
Author SHA1 Message Date
Jonathan A. Sternberg bf40c24e00 dap: improve location resolution for duplicate digests
This improves location resolution for duplicate digests by making some
assumptions about the file structure to determine a "best match" when
there are multiple possible locations.

It uses the next operation (that this digest is the input for) to
determine a location. If the location of the current operation is before
the next operation, this location is preferred. If there are multiple
locations that happen before the next operation, the one closest to the
next operation (aka later in the file) is used instead.

This resolves the most common case of multiple identical `FROM`
statements without adding more code to the frontends themselves.

Signed-off-by: Jonathan A. Sternberg <jonathan.sternberg@docker.com>
2025-09-04 15:04:06 -05:00
Jonathan A. Sternberg b3c389690c dap: look for base name of dockerfile name instead of path from context
When the builder loads a dockerfile, it does it by using the base name
of the dockerfile path and only loads the innermost directory. This
means that the source name we're looking for is the base name and not
the full relative path.

Update the set breakpoints functionality so it takes this into account.
Fixes scenarios where DAP is used with a dockerfile nested in the
context.

Signed-off-by: Jonathan A. Sternberg <jonathan.sternberg@docker.com>
2025-08-15 14:41:00 -05:00
Jonathan A. Sternberg 8e356c3454 dap: filesystem inspection when paused on a digest
Add a file explorer to the debugger that allows exploring the filesystem
of the current container. It will show directory contents, file
contents, and symlink destinations. It will also show the file mode
associated with a file.

The file explorer defaults to marking itself as an expensive operation
so the debugger doesn't automatically retrieve the information.

Signed-off-by: Jonathan A. Sternberg <jonathan.sternberg@docker.com>
2025-07-28 09:52:30 -05:00
Jonathan A. Sternberg 1e3c44709d dap: refactor how step in/step out works
Change how breakpoints and stepping works. These now work more how you
would expect another programming language to work. Breakpoints happen
before the step has been invoked rather than after which means you can
inspect the state before the command runs.

This has the advantage of being more intuitive for someone familiar with
other debuggers. The negative is that you can't run to after a certain
step as easily as you could before. Instead, you would run to that stage
and then use next to go to the step directly afterwards.

Step in and out also now have different behaviors. When a step has
multiple inputs, the inputs of non-zero index are considered like
"function calls". The most common cause of this is to use `COPY --from`
or a bind mount. Stepping into these will cause it to jump to the
beginning of the call chain for that branch. Using step out will exit
back to the location where step in was used.

This change also makes it so some steps may be invoked multiple times in
the callgraph if multiple steps depend on them. The reused steps will
still be cached, but you may end up stepping through more lines than the
previous implementation.

Stack traces now represent where these step in and step out areas
happen rather than the previous steps. This can help you know from where
a certain step is being used.

Signed-off-by: Jonathan A. Sternberg <jonathan.sternberg@docker.com>
2025-07-23 17:10:40 -05:00
Jonathan A. Sternberg 1886e232c5 dap: implement variable references
Implement variable references to inspect the state of a stack frame.

Variable reference ids are composed of two sections. A thread mask that
is the first 8 bytes and the remainder is an increasing number that gets
reset each time a thread is resumed. This allows the adapter to know
which thread to delegate the variables request to and allows the
variable references to still remain confined to each thread. An int32 is
used for this because variable references need to be in the range of
(0, 2^32).

At the moment, only the platform variables and some of the exec
operations for an operation. These are labeled as "arguments" to the
stack frame.

Signed-off-by: Jonathan A. Sternberg <jonathan.sternberg@docker.com>
2025-07-14 10:59:05 -05:00