README
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Hitsumabushi (ひつまぶし)
Package hitsumabushi provides APIs to generate JSON for go-build's -overlay option.
Hitsumabushi aims to make Go programs work on almost everywhere by overwriting system calls with C function calls.
Now the generated JSON works only for Linux/Arm64 and Windows/Amd64 so far.
For GOOS=windows, Hitsumabushi replaces some functions that don't work on some special Windows-like systems.
Go version: 1.19-1.21
Example
On Arm Linux, run these commands:
cd example/helloworld
./run.sh
Tips
With VC++, you might have to call _rt0_amd64_windows_lib() at the beginning of the entry point explicitly.
See also https://github.com/golang/go/issues/42190.
Documentation
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Overview ¶
Package hitsumabushi provides APIs to generate JSON for go-build's `-overlay` option. Hitsumabushi aims to make Go programs work on almost everywhere by overwriting system calls with C function calls. Now the generated JSON works only for Arm64 so far.
Index ¶
- func CPUFilePath(os string) (string, error)
- func ClockFilePath(os string) (string, error)
- func FilesystemFilePath(os string) (string, error)
- func FutexFilePath(os string) (string, error)
- func GenOverlayJSON(options ...Option) ([]byte, error)
- func MemoryFilePath(os string) (string, error)
- func ThreadFilePath(os string) (string, error)
- type Option
Constants ¶
This section is empty.
Variables ¶
This section is empty.
Functions ¶
func CPUFilePath ¶
CPUFilePath returns a C file's path for the CPU functions. This file works only when linux is specified as the GOOS option.
The file includes this function:
- int32_t hitsumabushi_getproccount()
The default implementation uses 1.
func ClockFilePath ¶
ClockFilePath returns a C file's path for the clock functions. This file works only when linux is specified as the GOOS option.
The file includes this function:
- int hitsumabushi_clock_gettime(clockid_t clk_id, struct timespec *tp)
The default implementation calls clock_gettime.
func FilesystemFilePath ¶
FilesystemFilePath returns a C file's path for the filesystem functions. This file works only when linux is specified as the GOOS option.
The file includes these functions:
- int32_t hitsumabushi_closefd(int32_t fd)
- int32_t hitsumabushi_open(char *name, int32_t mode, int32_t perm)
- int32_t hitsumabushi_read(int32_t fd, void *p, int32_t n)
- int32_t hitsumabushi_write1(uintptr_t fd, void *p, int32_t n)
- int32_t hitsumabushi_lseek(uintptr_t fd, off_t offset, int32_t whence)
- int32_t hitsumabushi_fcntl(int32_t fd, int32_t cmd, int32_t arg)
- int32_t hitsumabushi_fstat(int32_t fd, struct stat *stat)
- int32_t hitsumabushi_renameat(int32_t fd1, char* name1, int32_t fd2, char* name2)
- int32_t hitsumabushi_fstatat(int32_t fd, char* name, struct stat* p, int32_t flags)
The default implementation only handles stdout, stderr, and some pseudo-files.
func FutexFilePath ¶
FutexFilePath returns a C file's path for the futex functions. This file works only when linux is specified as the GOOS option.
The file includes this function:
- int32_t hitsumabushi_futex(uint32_t *uaddr, int32_t futex_op, uint32_t val, const struct timespec *timeout, uint32_t *uaddr2, uint32_t val3)
The default implementation is a pseudo futex by pthread.
func GenOverlayJSON ¶
GenOverlayJSON generates a JSON file for go-build's `-overlay` option. GenOverlayJSON returns a JSON file content, or an error if generating it fails.
Now the generated JSON works only for Arm64 so far.
func MemoryFilePath ¶
MemoryFilePath returns a C file's path for the memory functions. This file works only when linux is specified as the GOOS option.
The file includes these functions:
- void* hitsumabushi_sysAllocOS(uintptr_t n)
- void hitsumabushi_sysUnusedOS(void* v, uintptr_t n)
- void hitsumabushi_sysUsedOS(void* v, uintptr_t n)
- void hitsumabushi_sysHugePageOS(void* v, uintptr_t n)
- void hitsumabushi_sysFreeOS(void* v, uintptr_t n)
- void hitsumabushi_sysFaultOS(void* v, uintptr_t n)
- void* hitsumabushi_sysReserveOS(void* v, uintptr_t n)
- void hitsumabushi_sysMapOS(void* v, uintptr_t n)
The default implementation is a pseudo allocation by calloc without free.
For the implementation details, see https://cs.opensource.google/go/go/+/master:src/runtime/mem.go .
func ThreadFilePath ¶
Types ¶
type Option ¶
type Option func(*config)
func OverlayDir ¶
OverlayDir sets the temporary working directory where overlay files are stored.
func PageSize ¶
PageSize specifies the page size. The deafult value is 4096.
This works only for Linux.
func ReplaceDLL ¶
ReplaceDLL replaces a DLL file name loaded at LoadLibraryW and LoadLibraryExW.
This works only for Windows.
Source Files
Directories