Summary:
There was some confusion in the code about how to represent process
environment. Most of the code (ab)used the Args class for this purpose,
but some of it used a more basic StringList class instead. In either
case, the fact that the underlying abstraction did not provide primitive
operations for the typical environment operations meant that even a
simple operation like checking for an environment variable value was
several lines of code.
This patch adds a separate Environment class, which is essentialy a
llvm::StringMap<std::string> in disguise. To standard StringMap
functionality, it adds a couple of new functions, which are specific to
the environment use case:
- (most important) envp conversion for passing into execve() and likes.
Instead of trying to maintain a constantly up-to-date envp view, it
provides a function which creates a envp view on demand, with the
expectation that this will be called as the very last thing before
handing the value to the system function.
- insert(StringRef KeyEqValue) - splits KeyEqValue into (key, value)
pair and inserts it into the environment map.
- compose(value_type KeyValue) - takes a map entry and converts in back
into "KEY=VALUE" representation.
With this interface most of the environment-manipulating code becomes
one-liners. The only tricky part was maintaining compatibility in
SBLaunchInfo, which expects that the environment entries are accessible
by index and that the returned const char* is backed by the launch info
object (random access into maps is hard and the map stores the entry in
a deconstructed form, so we cannot just return a .c_str() value). To
solve this, I have the SBLaunchInfo convert the environment into the
"envp" form, and use it to answer the environment queries. Extra code is
added to make sure the envp version is always in sync.
(This also improves the layering situation as Args was in the Interpreter module
whereas Environment is in Utility.)
Reviewers: zturner, davide, jingham, clayborg
Subscribers: emaste, lldb-commits, mgorny
Differential Revision: https://reviews.llvm.org/D41359
llvm-svn: 322174
Host::GetEnvironment returns a StringList, but the interface for
launching a process takes Args. The fact that we use two classes for
representing an environment is not ideal, but for now we should at least
have an easy way to convert between the two.
llvm-svn: 320366
Summary:
Use StringRef and ArrayRef where possible. This adds an accessor to the
Args class to get a view of the arguments as ArrayRef<const char *>.
Reviewers: zturner
Subscribers: lldb-commits
Differential Revision: https://reviews.llvm.org/D30402
llvm-svn: 296592
There were a number of issues with the Args class preventing
efficient use of strings and incoporating LLVM's StringRef class.
The two biggest were:
1. Backing memory stored in a std::string, so we would frequently
have to use const_cast to get a mutable buffer for passing to
various low level APIs.
2. backing std::strings stored in a std::list, which doesn't
provide random access.
I wanted to solve these two issues so that we could provide
StringRef access to the underlying arguments, and also a way
to provide range-based access to the underlying argument array
while still providing convenient c-style access via an argv style
const char**.
The solution here is to store arguments in a single "entry" class
which contains the backing memory, a StringRef with precomputed
length, and the quote char. The backing memory is a manually
allocated const char* so that it is not invalidated when the
container is resized, and there is a separate argv array provided
for c-style access.
Differential revision: https://reviews.llvm.org/D25099
llvm-svn: 283157
Also fixed up a couple misbehaving functions. It is perfectly
legal to have env vars with no values (i.e. the '=' and following
need not be present).
llvm-svn: 282171
This patch also marks the const char* versions as =delete to prevent
their use. This has the potential to cause build breakages on some
platforms which I can't compile. I have tested on Windows, Linux,
and OSX. Best practices for fixing broken callsites are outlined in
Args.h in a comment above the deleted function declarations.
Eventually we can remove these =delete declarations, but for now they
are important to make sure that all implicit conversions from
const char * are manually audited to make sure that they do not invoke a
conversion from nullptr.
llvm-svn: 281919
Where possible, remove the const char* version. To keep the
risk and impact here minimal, I've only done the simplest
functions.
In the process, I found a few opportunities for adding some
unit tests, so I added those as well.
Tested on Windows, Linux, and OSX.
llvm-svn: 281799
*** to conform to clang-format’s LLVM style. This kind of mass change has
*** two obvious implications:
Firstly, merging this particular commit into a downstream fork may be a huge
effort. Alternatively, it may be worth merging all changes up to this commit,
performing the same reformatting operation locally, and then discarding the
merge for this particular commit. The commands used to accomplish this
reformatting were as follows (with current working directory as the root of
the repository):
find . \( -iname "*.c" -or -iname "*.cpp" -or -iname "*.h" -or -iname "*.mm" \) -exec clang-format -i {} +
find . -iname "*.py" -exec autopep8 --in-place --aggressive --aggressive {} + ;
The version of clang-format used was 3.9.0, and autopep8 was 1.2.4.
Secondly, “blame” style tools will generally point to this commit instead of
a meaningful prior commit. There are alternatives available that will attempt
to look through this change and find the appropriate prior commit. YMMV.
llvm-svn: 280751
The order of libraries passed to the linker didn't work under linux (you
need the llvm libraries first, then the lldb libraries). I modelled this
after clang's setup here. Seemed simple enough to just be consistent.
llvm-svn: 232461
A recent refactor had introduced a bug where if you escaped a
character, the rest of the string would get processed incorrectly.
This patch fixes that bug and adds some unit tests for Args.
llvm-svn: 232288