This kind of thing is a bit annoying. On Serenity, size_t is the same
size as u32, but not the same type. Because of "long" or whatever.
This patch makes String not complain about duplicate overloads.
The former allows you to inspect the string while it's being built.
It's an explicit method rather than `operator StringView()` because
you must remember you can only look at it in between modifications;
appending to the StringBuilder invalidates the StringView.
The latter lets you clear the state of a StringBuilder explicitly, to
start from an empty string again.
This simplifies the ownership model and makes Region easier to reason
about. Userspace Regions are now primarily kept by Process::m_regions.
Kernel Regions are kept in various OwnPtr<Regions>'s.
Regions now only ever get unmapped when they are destroyed.
`AK::String` can now be reversed via AK::String::reverse(). This makes
life a lot easier for functions like `itoa()`, where the output
ends up being backwards. Very much not like the normal STL
(which requires an `std::reverse` object) way of doing things.
A call to reverse returns a new `AK::String` so as to not upset any
of the possible references to the same `StringImpl` shared between
Strings.
The old implementation tried to move forward as long as the current
byte looks like a UTF-8 character continuation byte (has its two
most significant bits set to 10). This is correct as long as we assume
the string is actually valid UTF-8, which we do (we also have a separate
method that can check whether it is the case).
We can't, however, assume that the data after the end of our string
is also valid UTF-8 (in fact, we're not even allowed to look at data
outside out string, but it happens to a valid memory region most of
the time). If the byte after the end of our string also has its most
significant bits set to 10, we would move one byte forward, and then
fail the m_length > 0 assertion.
One way to fix this would be to add a length check inside the loop
condition. The other one, implemented in this commit, is to reimplement
the whole function in terms of decode_first_byte(), which gives us
the length as encoded in the first byte. This also brings it more
in line with the other functions around it that do UTF-8 decoding.
This patch adds support for TLS according to the x86 System V ABI.
Each thread gets a thread-specific memory region, and the GS segment
register always points _to a pointer_ to the thread-specific memory.
In other words, to access thread-local variables, userspace programs
start by dereferencing the pointer at [gs:0].
The Process keeps a master copy of the TLS segment that new threads
should use, and when a new thread is created, they get a copy of it.
It's basically whatever the PT_TLS program header in the ELF says.
This was a workaround to be able to build on case-insensitive file
systems where it might get confused about <string.h> vs <String.h>.
Let's just not support building that way, so String.h can have an
objectively nicer name. :^)
Passing these through the generic JsonValue path was causing us to
instantiate temporary JsonValues that incurred a heap allocation.
This avoids that by adding specialized overloads for string types.
Right now if we encounter an unknown character, printf (and its related
functions) fail in a really bad way, where they forget to pull things off
the stack. This usually leads to a crash somewhere else, which is hard to
debug.
This patch makes printf abort as soon as it encounters a formatting
character that it can't handle. This is not the optimal solution, but it
is an improvement for debugging.
Utf8View wraps a StringView and implements begin() and end() that
return a Utf8CodepointIterator, which parses UTF-8-encoded Unicode
codepoints and returns them as 32-bit integers.
This is the first step towards supporting emojis in Serenity ^)
https://github.com/SerenityOS/serenity/issues/490
When printing hex numbers, we were printing the wrong thing sometimes. This
was because we were dividing the digit to print by 15 instead of 16. Also,
dividing by 16 is the same as shifting four bits to the right, which is a
bit closer to our actual intention in this case, so let's use a shift
instead.
This way, primitive JsonValue serialization is still handled by
JsonValue::serialize(), but JsonArray and JsonObject serialization
always goes through serializer classes. This is no less efficient
if you have the whole JSON in memory already.
We use consumable annotations to catch bugs where you get the .value()
of an Optional before verifying that it's okay.
The bug here was that only has_value() would set the consumed state,
even though operator bool() does the same job.
Normally you want to access the T&, but sometimes you need to grab at
the NonnullPtr, for example when moving it out of the Vector before
a call to remove(). This is generally a weird pattern, but I don't have
a better solution at the moment.
Using the new get_process_name() syscall, we can automatically prefix
all userspace debug logging.
Hopefully this is more helpful than annoying. We'll find out! :^)
