796 lines
16 KiB
C
796 lines
16 KiB
C
// (‑●‑●)> dual licensed under the WTFPL v2 and MIT licenses
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// without any warranty.
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// by Gregory Pakosz (@gpakosz)
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// https://github.com/gpakosz/whereami
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// in case you want to #include "whereami.c" in a larger compilation unit
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#if !defined(WHEREAMI_H)
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#include <whereami.h>
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#endif
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#ifdef __cplusplus
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extern "C" {
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#endif
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#if !defined(WAI_MALLOC) || !defined(WAI_FREE) || !defined(WAI_REALLOC)
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#include <stdlib.h>
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#endif
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#if !defined(WAI_MALLOC)
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#define WAI_MALLOC(size) malloc(size)
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#endif
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#if !defined(WAI_FREE)
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#define WAI_FREE(p) free(p)
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#endif
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#if !defined(WAI_REALLOC)
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#define WAI_REALLOC(p, size) realloc(p, size)
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#endif
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#ifndef WAI_NOINLINE
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#if defined(_MSC_VER)
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#define WAI_NOINLINE __declspec(noinline)
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#elif defined(__GNUC__)
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#define WAI_NOINLINE __attribute__((noinline))
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#else
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#error unsupported compiler
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#endif
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#endif
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#if defined(_MSC_VER)
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#define WAI_RETURN_ADDRESS() _ReturnAddress()
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#elif defined(__GNUC__)
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#define WAI_RETURN_ADDRESS() __builtin_extract_return_addr(__builtin_return_address(0))
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#else
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#error unsupported compiler
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#endif
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#if defined(_WIN32)
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#ifndef WIN32_LEAN_AND_MEAN
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#define WIN32_LEAN_AND_MEAN
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#endif
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#if defined(_MSC_VER)
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#pragma warning(push, 3)
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#endif
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#include <windows.h>
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#include <intrin.h>
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#if defined(_MSC_VER)
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#pragma warning(pop)
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#endif
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#include <stdbool.h>
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static int WAI_PREFIX(getModulePath_)(HMODULE module, char* out, int capacity, int* dirname_length)
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{
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wchar_t buffer1[MAX_PATH];
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wchar_t buffer2[MAX_PATH];
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wchar_t* path = NULL;
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int length = -1;
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bool ok;
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for (ok = false; !ok; ok = true)
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{
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DWORD size;
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int length_, length__;
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size = GetModuleFileNameW(module, buffer1, sizeof(buffer1) / sizeof(buffer1[0]));
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if (size == 0)
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break;
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else if (size == (DWORD)(sizeof(buffer1) / sizeof(buffer1[0])))
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{
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DWORD size_ = size;
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do
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{
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wchar_t* path_;
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path_ = (wchar_t*)WAI_REALLOC(path, sizeof(wchar_t) * size_ * 2);
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if (!path_)
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break;
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size_ *= 2;
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path = path_;
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size = GetModuleFileNameW(module, path, size_);
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}
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while (size == size_);
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if (size == size_)
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break;
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}
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else
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path = buffer1;
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if (!_wfullpath(buffer2, path, MAX_PATH))
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break;
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length_ = (int)wcslen(buffer2);
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length__ = WideCharToMultiByte(CP_UTF8, 0, buffer2, length_ , out, capacity, NULL, NULL);
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if (length__ == 0)
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length__ = WideCharToMultiByte(CP_UTF8, 0, buffer2, length_, NULL, 0, NULL, NULL);
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if (length__ == 0)
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break;
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if (length__ <= capacity && dirname_length)
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{
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int i;
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for (i = length__ - 1; i >= 0; --i)
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{
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if (out[i] == '\\')
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{
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*dirname_length = i;
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break;
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}
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}
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}
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length = length__;
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}
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if (path != buffer1)
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WAI_FREE(path);
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return ok ? length : -1;
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}
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WAI_NOINLINE WAI_FUNCSPEC
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int WAI_PREFIX(getExecutablePath)(char* out, int capacity, int* dirname_length)
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{
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return WAI_PREFIX(getModulePath_)(NULL, out, capacity, dirname_length);
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}
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WAI_NOINLINE WAI_FUNCSPEC
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int WAI_PREFIX(getModulePath)(char* out, int capacity, int* dirname_length)
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{
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HMODULE module;
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int length = -1;
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#if defined(_MSC_VER)
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#pragma warning(push)
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#pragma warning(disable: 4054)
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#endif
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if (GetModuleHandleEx(GET_MODULE_HANDLE_EX_FLAG_FROM_ADDRESS | GET_MODULE_HANDLE_EX_FLAG_UNCHANGED_REFCOUNT, (LPCTSTR)WAI_RETURN_ADDRESS(), &module))
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#if defined(_MSC_VER)
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#pragma warning(pop)
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#endif
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{
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length = WAI_PREFIX(getModulePath_)(module, out, capacity, dirname_length);
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}
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return length;
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}
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#elif defined(__linux__) || defined(__CYGWIN__) || defined(__sun) || defined(WAI_USE_PROC_SELF_EXE)
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#if defined(__linux__)
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#include <linux/limits.h>
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#else
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#include <limits.h>
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#endif
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#ifndef __STDC_FORMAT_MACROS
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#define __STDC_FORMAT_MACROS
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#endif
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#include <inttypes.h>
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#include <stdbool.h>
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#if !defined(WAI_PROC_SELF_EXE)
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#if defined(__sun)
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#define WAI_PROC_SELF_EXE "/proc/self/path/a.out"
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#else
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#define WAI_PROC_SELF_EXE "/proc/self/exe"
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#endif
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#endif
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WAI_FUNCSPEC
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int WAI_PREFIX(getExecutablePath)(char* out, int capacity, int* dirname_length)
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{
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char buffer[PATH_MAX];
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char* resolved = NULL;
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int length = -1;
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bool ok;
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for (ok = false; !ok; ok = true)
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{
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resolved = realpath(WAI_PROC_SELF_EXE, buffer);
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if (!resolved)
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break;
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length = (int)strlen(resolved);
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if (length <= capacity)
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{
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memcpy(out, resolved, length);
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if (dirname_length)
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{
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int i;
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for (i = length - 1; i >= 0; --i)
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{
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if (out[i] == '/')
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{
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*dirname_length = i;
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break;
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}
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}
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}
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}
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}
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return ok ? length : -1;
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}
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#if !defined(WAI_PROC_SELF_MAPS_RETRY)
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#define WAI_PROC_SELF_MAPS_RETRY 5
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#endif
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#if !defined(WAI_PROC_SELF_MAPS)
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#if defined(__sun)
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#define WAI_PROC_SELF_MAPS "/proc/self/map"
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#else
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#define WAI_PROC_SELF_MAPS "/proc/self/maps"
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#endif
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#endif
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#if defined(__ANDROID__) || defined(ANDROID)
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#include <fcntl.h>
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#include <sys/mman.h>
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#include <unistd.h>
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#endif
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#include <stdbool.h>
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WAI_NOINLINE WAI_FUNCSPEC
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int WAI_PREFIX(getModulePath)(char* out, int capacity, int* dirname_length)
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{
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int length = -1;
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FILE* maps = NULL;
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for (int r = 0; r < WAI_PROC_SELF_MAPS_RETRY; ++r)
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{
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maps = fopen(WAI_PROC_SELF_MAPS, "r");
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if (!maps)
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break;
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for (;;)
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{
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char buffer[PATH_MAX < 1024 ? 1024 : PATH_MAX];
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uint64_t low, high;
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char perms[5];
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uint64_t offset;
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uint32_t major, minor;
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char path[PATH_MAX];
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uint32_t inode;
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if (!fgets(buffer, sizeof(buffer), maps))
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break;
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if (sscanf(buffer, "%" PRIx64 "-%" PRIx64 " %s %" PRIx64 " %x:%x %u %s\n", &low, &high, perms, &offset, &major, &minor, &inode, path) == 8)
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{
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uint64_t addr = (uintptr_t)WAI_RETURN_ADDRESS();
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if (low <= addr && addr <= high)
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{
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char* resolved;
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resolved = realpath(path, buffer);
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if (!resolved)
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break;
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length = (int)strlen(resolved);
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#if defined(__ANDROID__) || defined(ANDROID)
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if (length > 4
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&&buffer[length - 1] == 'k'
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&&buffer[length - 2] == 'p'
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&&buffer[length - 3] == 'a'
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&&buffer[length - 4] == '.')
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{
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int fd = open(path, O_RDONLY);
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if (fd == -1)
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{
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length = -1; // retry
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break;
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}
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char* begin = (char*)mmap(0, offset, PROT_READ, MAP_SHARED, fd, 0);
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if (begin == MAP_FAILED)
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{
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close(fd);
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length = -1; // retry
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break;
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}
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char* p = begin + offset - 30; // minimum size of local file header
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while (p >= begin) // scan backwards
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{
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if (*((uint32_t*)p) == 0x04034b50UL) // local file header signature found
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{
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uint16_t length_ = *((uint16_t*)(p + 26));
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if (length + 2 + length_ < (int)sizeof(buffer))
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{
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memcpy(&buffer[length], "!/", 2);
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memcpy(&buffer[length + 2], p + 30, length_);
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length += 2 + length_;
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}
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break;
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}
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--p;
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}
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munmap(begin, offset);
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close(fd);
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}
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#endif
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if (length <= capacity)
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{
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memcpy(out, resolved, length);
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if (dirname_length)
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{
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int i;
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for (i = length - 1; i >= 0; --i)
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{
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if (out[i] == '/')
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{
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*dirname_length = i;
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break;
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}
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}
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}
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}
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break;
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}
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}
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}
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fclose(maps);
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maps = NULL;
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if (length != -1)
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break;
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}
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return length;
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}
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#elif defined(__APPLE__)
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#define _DARWIN_BETTER_REALPATH
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#include <mach-o/dyld.h>
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#include <limits.h>
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#include <stdlib.h>
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#include <string.h>
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#include <dlfcn.h>
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#include <stdbool.h>
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WAI_FUNCSPEC
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int WAI_PREFIX(getExecutablePath)(char* out, int capacity, int* dirname_length)
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{
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char buffer1[PATH_MAX];
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char buffer2[PATH_MAX];
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char* path = buffer1;
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char* resolved = NULL;
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int length = -1;
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bool ok;
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for (ok = false; !ok; ok = true)
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{
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uint32_t size = (uint32_t)sizeof(buffer1);
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if (_NSGetExecutablePath(path, &size) == -1)
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{
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path = (char*)WAI_MALLOC(size);
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if (!_NSGetExecutablePath(path, &size))
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break;
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}
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resolved = realpath(path, buffer2);
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if (!resolved)
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break;
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length = (int)strlen(resolved);
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if (length <= capacity)
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{
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memcpy(out, resolved, length);
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if (dirname_length)
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{
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int i;
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for (i = length - 1; i >= 0; --i)
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{
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if (out[i] == '/')
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{
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*dirname_length = i;
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break;
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}
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}
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}
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}
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}
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if (path != buffer1)
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WAI_FREE(path);
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return ok ? length : -1;
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}
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WAI_NOINLINE WAI_FUNCSPEC
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int WAI_PREFIX(getModulePath)(char* out, int capacity, int* dirname_length)
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{
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char buffer[PATH_MAX];
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char* resolved = NULL;
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int length = -1;
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for(;;)
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{
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Dl_info info;
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if (dladdr(WAI_RETURN_ADDRESS(), &info))
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{
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resolved = realpath(info.dli_fname, buffer);
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if (!resolved)
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break;
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length = (int)strlen(resolved);
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if (length <= capacity)
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{
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memcpy(out, resolved, length);
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if (dirname_length)
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{
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int i;
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for (i = length - 1; i >= 0; --i)
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{
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if (out[i] == '/')
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{
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*dirname_length = i;
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break;
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}
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}
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}
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}
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}
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break;
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}
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return length;
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}
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#elif defined(__QNXNTO__)
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#include <limits.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <dlfcn.h>
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#include <stdbool.h>
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#if !defined(WAI_PROC_SELF_EXE)
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#define WAI_PROC_SELF_EXE "/proc/self/exefile"
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#endif
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WAI_FUNCSPEC
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int WAI_PREFIX(getExecutablePath)(char* out, int capacity, int* dirname_length)
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{
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char buffer1[PATH_MAX];
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char buffer2[PATH_MAX];
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char* resolved = NULL;
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FILE* self_exe = NULL;
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int length = -1;
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bool ok;
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for (ok = false; !ok; ok = true)
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{
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self_exe = fopen(WAI_PROC_SELF_EXE, "r");
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if (!self_exe)
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break;
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if (!fgets(buffer1, sizeof(buffer1), self_exe))
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break;
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resolved = realpath(buffer1, buffer2);
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if (!resolved)
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break;
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length = (int)strlen(resolved);
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if (length <= capacity)
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{
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memcpy(out, resolved, length);
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if (dirname_length)
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{
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int i;
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for (i = length - 1; i >= 0; --i)
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{
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if (out[i] == '/')
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{
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*dirname_length = i;
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break;
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}
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}
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}
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}
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}
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fclose(self_exe);
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return ok ? length : -1;
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}
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WAI_FUNCSPEC
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int WAI_PREFIX(getModulePath)(char* out, int capacity, int* dirname_length)
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{
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char buffer[PATH_MAX];
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char* resolved = NULL;
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int length = -1;
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for(;;)
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{
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Dl_info info;
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if (dladdr(WAI_RETURN_ADDRESS(), &info))
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{
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resolved = realpath(info.dli_fname, buffer);
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if (!resolved)
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break;
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length = (int)strlen(resolved);
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if (length <= capacity)
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{
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memcpy(out, resolved, length);
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if (dirname_length)
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{
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int i;
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for (i = length - 1; i >= 0; --i)
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{
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if (out[i] == '/')
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{
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*dirname_length = i;
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break;
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}
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}
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}
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}
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}
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break;
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}
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return length;
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}
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#elif defined(__DragonFly__) || defined(__FreeBSD__) || \
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defined(__FreeBSD_kernel__) || defined(__NetBSD__) || defined(__OpenBSD__)
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#include <limits.h>
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#include <stdlib.h>
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#include <string.h>
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#include <sys/types.h>
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#include <sys/sysctl.h>
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#include <dlfcn.h>
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#include <stdbool.h>
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#if defined(__OpenBSD__)
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#include <unistd.h>
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WAI_FUNCSPEC
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int WAI_PREFIX(getExecutablePath)(char* out, int capacity, int* dirname_length)
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{
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char buffer1[4096];
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char buffer2[PATH_MAX];
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char buffer3[PATH_MAX];
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char** argv = (char**)buffer1;
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char* resolved = NULL;
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int length = -1;
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bool ok;
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for (ok = false; !ok; ok = true)
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{
|
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int mib[4] = { CTL_KERN, KERN_PROC_ARGS, getpid(), KERN_PROC_ARGV };
|
|
size_t size;
|
|
|
|
if (sysctl(mib, 4, NULL, &size, NULL, 0) != 0)
|
|
break;
|
|
|
|
if (size > sizeof(buffer1))
|
|
{
|
|
argv = (char**)WAI_MALLOC(size);
|
|
if (!argv)
|
|
break;
|
|
}
|
|
|
|
if (sysctl(mib, 4, argv, &size, NULL, 0) != 0)
|
|
break;
|
|
|
|
if (strchr(argv[0], '/'))
|
|
{
|
|
resolved = realpath(argv[0], buffer2);
|
|
if (!resolved)
|
|
break;
|
|
}
|
|
else
|
|
{
|
|
const char* PATH = getenv("PATH");
|
|
if (!PATH)
|
|
break;
|
|
|
|
size_t argv0_length = strlen(argv[0]);
|
|
|
|
const char* begin = PATH;
|
|
while (1)
|
|
{
|
|
const char* separator = strchr(begin, ':');
|
|
const char* end = separator ? separator : begin + strlen(begin);
|
|
|
|
if (end - begin > 0)
|
|
{
|
|
if (*(end -1) == '/')
|
|
--end;
|
|
|
|
if (((end - begin) + 1 + argv0_length + 1) <= sizeof(buffer2))
|
|
{
|
|
memcpy(buffer2, begin, end - begin);
|
|
buffer2[end - begin] = '/';
|
|
memcpy(buffer2 + (end - begin) + 1, argv[0], argv0_length + 1);
|
|
|
|
resolved = realpath(buffer2, buffer3);
|
|
if (resolved)
|
|
break;
|
|
}
|
|
}
|
|
|
|
if (!separator)
|
|
break;
|
|
|
|
begin = ++separator;
|
|
}
|
|
|
|
if (!resolved)
|
|
break;
|
|
}
|
|
|
|
length = (int)strlen(resolved);
|
|
if (length <= capacity)
|
|
{
|
|
memcpy(out, resolved, length);
|
|
|
|
if (dirname_length)
|
|
{
|
|
int i;
|
|
|
|
for (i = length - 1; i >= 0; --i)
|
|
{
|
|
if (out[i] == '/')
|
|
{
|
|
*dirname_length = i;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
if (argv != (char**)buffer1)
|
|
WAI_FREE(argv);
|
|
|
|
return ok ? length : -1;
|
|
}
|
|
|
|
#else
|
|
|
|
WAI_FUNCSPEC
|
|
int WAI_PREFIX(getExecutablePath)(char* out, int capacity, int* dirname_length)
|
|
{
|
|
char buffer1[PATH_MAX];
|
|
char buffer2[PATH_MAX];
|
|
char* path = buffer1;
|
|
char* resolved = NULL;
|
|
int length = -1;
|
|
bool ok;
|
|
|
|
for (ok = false; !ok; ok = true)
|
|
{
|
|
#if defined(__NetBSD__)
|
|
int mib[4] = { CTL_KERN, KERN_PROC_ARGS, -1, KERN_PROC_PATHNAME };
|
|
#else
|
|
int mib[4] = { CTL_KERN, KERN_PROC, KERN_PROC_PATHNAME, -1 };
|
|
#endif
|
|
size_t size = sizeof(buffer1);
|
|
|
|
if (sysctl(mib, 4, path, &size, NULL, 0) != 0)
|
|
break;
|
|
|
|
resolved = realpath(path, buffer2);
|
|
if (!resolved)
|
|
break;
|
|
|
|
length = (int)strlen(resolved);
|
|
if (length <= capacity)
|
|
{
|
|
memcpy(out, resolved, length);
|
|
|
|
if (dirname_length)
|
|
{
|
|
int i;
|
|
|
|
for (i = length - 1; i >= 0; --i)
|
|
{
|
|
if (out[i] == '/')
|
|
{
|
|
*dirname_length = i;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
return ok ? length : -1;
|
|
}
|
|
|
|
#endif
|
|
|
|
WAI_NOINLINE WAI_FUNCSPEC
|
|
int WAI_PREFIX(getModulePath)(char* out, int capacity, int* dirname_length)
|
|
{
|
|
char buffer[PATH_MAX];
|
|
char* resolved = NULL;
|
|
int length = -1;
|
|
|
|
for(;;)
|
|
{
|
|
Dl_info info;
|
|
|
|
if (dladdr(WAI_RETURN_ADDRESS(), &info))
|
|
{
|
|
resolved = realpath(info.dli_fname, buffer);
|
|
if (!resolved)
|
|
break;
|
|
|
|
length = (int)strlen(resolved);
|
|
if (length <= capacity)
|
|
{
|
|
memcpy(out, resolved, length);
|
|
|
|
if (dirname_length)
|
|
{
|
|
int i;
|
|
|
|
for (i = length - 1; i >= 0; --i)
|
|
{
|
|
if (out[i] == '/')
|
|
{
|
|
*dirname_length = i;
|
|
break;
|
|
}
|
|
}
|
|
}
|
|
}
|
|
}
|
|
|
|
break;
|
|
}
|
|
|
|
return length;
|
|
}
|
|
|
|
#else
|
|
|
|
#error unsupported platform
|
|
|
|
#endif
|
|
|
|
#ifdef __cplusplus
|
|
}
|
|
#endif |