Adds Windows stub (still needs to be implemented on Windows),
adds WASI implementation, adds unit test testing basic chain of
ops: create file -> symlink -> readlink.
* `std.fs.Dir.Entry.Kind` is moved to `std.fs.File.Kind`
* `std.fs.File.Stat` gains the `kind` field, so performing a stat() on
a File now tells what kind of file it is. On Windows this only will
distinguish between directories and files.
* rework zig fmt logic so that in the case of opening a file and
discovering it to be a directory, it closes the file descriptor
before re-opening it with O_DIRECTORY, using fewer simultaneous open
file descriptors when walking a directory tree.
* rework zig fmt logic so that it pays attention to the kind of
directory entries, and when it sees a sub-directory it attempts to
open it as a directory rather than a file, reducing the number of
open() syscalls when walking a directory tree.
* Take advantage of coercing anonymous struct literals to struct types.
* Reworks Module to favor Zig source as the primary use case.
Breaks ZIR compilation, which will have to be restored in a future commit.
* Decl uses src_index rather then src, pointing to an AST Decl node
index, or ZIR Module Decl index, rather than a byte offset.
* ZIR instructions have an `analyzed_inst` field instead of Module
having a hash table.
* Module.Fn loses the `fn_type` field since it is redundant with
its `owner_decl` `TypedValue` type.
* Implement Type and Value copying. A ZIR Const instruction's TypedValue
is copied to the Decl arena during analysis, which allows freeing the
ZIR text instructions post-analysis.
* Don't flush the ELF file if there are compilation errors.
* Function return types allow arbitrarily complex expressions.
* AST->ZIR for function calls and return statements.
* Introduce the concept of anonymous Decls
* Primitive Hello, World with inline asm works
* There is still an unsolved problem of how to manage ZIR instructions
memory when generating from AST. Currently it leaks.
One of the main motivating use cases for this language feature is
tracing/profiling tools, which expect null-terminated strings for these
values. Since the data is statically allocated, making them
additionally null-terminated comes at no cost.
This prevents the requirement of compile-time code to convert to
null-termination, which could increase the compilation time of
code with tracing enabled.
See #2029
std.log provides 8 log levels and corresponding logging functions. It
allows the user to override the logging "backend" by defining root.log
and to override the default log level by defining root.log_level.
Logging functions accept a scope parameter which allows the implementer
of the logging "backend" to filter logging by library as well as level.
Using the standardized syslog [1] log levels ensures that std.log will
be flexible enough to work for as many use-cases as possible. If we were
to stick with only 3/4 log levels, std.log would be insufficient for
large and/or complex projects such as a kernel or display server.
[1]: https://tools.ietf.org/html/rfc5424#section-6.2.1
- stderr_file_writer was unused
- stderr_stream was a pointer to a stream, rather than a stream
- other functions assumed that getStderrStream has already been called
