When checking the `left` argument, it previously allowed having
left == len. However, this means the substring starts one past the last
character in the string and should return the empty string. In practice,
this already worked correctly, because buffer[len] contains the trailing
nul, so it would (re)assign the empty string to `out`.
However, fixing this check makes it a bit more logical, and prevents a
fairly unlikely out-of-buffer write (to address 0x0) when calling
substring on an invalidated String:
String bar = (char*)NULL;
bar.substring(0, 0);
Previously, this method calculated the length of the string from the
given index onwards. However, the other remove() method called already
contains code for this calculation, which is used when the count passed
in is too big. This means we can just pass in a very big count that is
guaranteed to point past the end of the string, shrinking the remove
method by a few bytes.
Previously, if you passed in a very big index and/or count, the
`index + count` could overflow, making the count be used as-is instead
of being truncated (causing the string to be updated wrongly and
potentially writing to arbitrary memory locations).
We can rewrite the comparison to use `len - index` instead. Since we
know that index < len, we are sure this subtraction does not overflow,
regardless of what values of index and count we pass in.
As an added bonus, the `len - index` value already needed be calculated
inside the if, so this saves a few instructions in the generated code.
To illustrate this problem, consider this code:
String foo = "foo";
Serial.println(foo.length()); // Prints 3
foo.remove(1, 65535); // Should remove all but first character
Serial.println(foo.length()); // Prints 4 without this patch
Not shown in this is example is that some arbitrary memory is written
as well.
The following empty stubs has been replaced by the gcc
flag -fno-threadsafe-static:
int __cxa_guard_acquire(__guard *);
void __cxa_guard_release (__guard *);
void __cxa_guard_abort (__guard *);
The following empty stubs has been moved into their specific
module abi.cpp:
void __cxa_pure_virtual(void) __attribute ((noreturn));
void __cxa_deleted_virtual(void) __attribute ((noreturn));
Fix#107
In the preferences dialog, the name of the preferences file is shown for
advanced editing. If the filename is clicked, the folder containing the
file is opened. However, this always used Base.getSettingsFolder, which
is the folder where the settings file _normally_ resides. But when the
--preferences-file option is used, the actual preferences file might be
somewhere else.
This commit makes sure to always open up the parent directory of the
actual preferences file in use, instead of always the default one.
When no build.path preference is present, a temporary directory is
automatically created (and deleted). When a build.path was specified,
but the directory does not exist, the IDE would show an error and fail
to build, which is unexpected and not so friendly.
This commit makes sure that the build directory is automatically
created.
Before, these were only shown in the GUI, which makes a failing
commandline build a bit puzzling. As a side effect, the error is now
shown in the log area in addition to the status line above the log
area, but that should be ok.
