UNLOZE/sourcemod
10
0
Fork 0
Code Issues Pull Requests Releases Wiki Activity

Add support for Mac OS X to ResolveSymbol() and FindPattern() in IMemUtils (bug 4392, r=dvander).

Browse Source
This commit is contained in:
Scott Ehlert 2010-05-13 04:20:41 -05:00
parent 31f223bff5
commit 5ef40e15c4
3 changed files with 214 additions and 27 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

216
core/MemoryUtils.cpp
View File

@ -2,7 +2,7 @@
* vim: set ts=4 sw=4 tw=99 noet :
* =============================================================================
* SourceMod
* Copyright (C) 2004-2009 AlliedModders LLC. All rights reserved.
* Copyright (C) 2004-2010 AlliedModders LLC. All rights reserved.
* =============================================================================
*
* This program is free software; you can redistribute it and/or modify it under
@ -34,30 +34,31 @@
#include <link.h>
#include <sys/mman.h>
#endif
#ifdef PLATFORM_APPLE
#include <mach-o/dyld_images.h>
#include <mach-o/loader.h>
#include <mach-o/nlist.h>
#endif
MemoryUtils g_MemUtils;
#if 0
MemoryUtils::MemoryUtils()
{
#ifdef PLATFORM_WINDOWS
#ifdef PLATFORM_APPLE
SYSTEM_INFO info;
GetSystemInfo(&info);
m_PageSize = info.dwPageSize;
#elif defined PLATFORM_POSIX
m_PageSize = sysconf(_SC_PAGE_SIZE);
/* Get pointer to struct that describes all loaded mach-o images in process */
struct nlist list[2];
memset(list, 0, sizeof(list));
list[0].n_un.n_name = (char *)"_dyld_all_image_infos";
nlist("/usr/lib/dyld", list);
m_ImageList = (struct dyld_all_image_infos *)list[0].n_value;
#endif
}
#endif
MemoryUtils::~MemoryUtils()
{
#ifdef PLATFORM_LINUX
#if defined PLATFORM_LINUX || defined PLATFORM_APPLE
for (size_t i = 0; i < m_SymTables.size(); i++)
{
delete m_SymTables[i];
@ -113,7 +114,7 @@ void *MemoryUtils::ResolveSymbol(void *handle, const char *symbol)
#ifdef PLATFORM_WINDOWS
return GetProcAddress((HMODULE)handle, symbol);
#elif defined PLATFORM_LINUX
struct link_map *dlmap;
@ -248,12 +249,140 @@ void *MemoryUtils::ResolveSymbol(void *handle, const char *symbol)
munmap(file_hdr, dlstat.st_size);
return symbol_entry ? symbol_entry->address : NULL;
#elif defined PLATFORM_APPLE
uintptr_t dlbase;
uint32_t image_count;
struct mach_header *file_hdr;
struct load_command *loadcmds;
struct symtab_command *symtab_hdr;
struct nlist *symtab;
const char *strtab;
uint32_t loadcmd_count;
uint32_t symbol_count;
LibSymbolTable *libtable;
SymbolTable *table;
Symbol *symbol_entry;
dlbase = 0;
image_count = m_ImageList->infoArrayCount;
symtab_hdr = NULL;
/* Loop through mach-o images in process.
* We can skip index 0 since that is just the executable.
*/
for (uint32_t i = 1; i < image_count; i++)
{
const struct dyld_image_info &info = m_ImageList->infoArray[i];
/* "Load" each one until we get a matching handle */
void *h = dlopen(info.imageFilePath, RTLD_NOLOAD);
if (h == handle)
{
dlbase = (uintptr_t)info.imageLoadAddress;
dlclose(h);
break;
}
dlclose(h);
}
if (!dlbase)
{
/* Uh oh, we couldn't find a matching handle */
return NULL;
}
/* See if we already have a symbol table for this library */
for (size_t i = 0; i < m_SymTables.size(); i++)
{
libtable = m_SymTables[i];
if (libtable->lib_base == dlbase)
{
table = &libtable->table;
break;
}
}
/* If we don't have a symbol table for this library, then create one */
if (table == NULL)
{
libtable = new LibSymbolTable();
libtable->table.Initialize();
libtable->lib_base = dlbase;
libtable->last_pos = 0;
table = &libtable->table;
m_SymTables.push_back(libtable);
}
/* See if the symbol is already cached in our table */
symbol_entry = table->FindSymbol(symbol, strlen(symbol));
if (symbol_entry != NULL)
{
return symbol_entry->address;
}
/* If symbol isn't in our table, then we have to locate it in memory */
file_hdr = (struct mach_header *)dlbase;
loadcmds = (struct load_command *)(dlbase + sizeof(struct mach_header));
loadcmd_count = file_hdr->ncmds;
/* Loop through load commands until we find the one for the symbol table */
for (uint32_t i = 0; i < loadcmd_count; i++)
{
if (loadcmds->cmd == LC_SYMTAB)
{
symtab_hdr = (struct symtab_command *)loadcmds;
break;
}
/* Load commands are not of a fixed size which is why we add the size */
loadcmds = (struct load_command *)((uintptr_t)loadcmds + loadcmds->cmdsize);
}
if (!symtab_hdr || !symtab_hdr->symoff || !symtab_hdr->stroff)
{
/* Uh oh, no symbol table */
return NULL;
}
symtab = (struct nlist *)(dlbase + symtab_hdr->symoff);
strtab = (const char *)(dlbase + symtab_hdr->stroff);
symbol_count = symtab_hdr->nsyms;
/* Iterate symbol table starting from the position we were at last time */
for (uint32_t i = libtable->last_pos; i < symbol_count; i++)
{
struct nlist &sym = symtab[i];
/* Ignore the prepended underscore on all symbols, so +1 here */
const char *sym_name = strtab + sym.n_un.n_strx + 1;
Symbol *cur_sym;
/* Skip symbols that are undefined */
if (sym.n_sect == NO_SECT)
{
continue;
}
/* Caching symbols as we go along */
cur_sym = table->InternSymbol(sym_name, strlen(sym_name), (void *)(dlbase + sym.n_value));
if (strcmp(symbol, sym_name) == 0)
{
symbol_entry = cur_sym;
libtable->last_pos = ++i;
break;
}
}
return symbol_entry ? symbol_entry->address : NULL;
#endif
}
bool MemoryUtils::GetLibraryInfo(const void *libPtr, DynLibInfo &lib)
{
unsigned long baseAddr;
uintptr_t baseAddr;
if (libPtr == NULL)
{
@ -273,7 +402,7 @@ bool MemoryUtils::GetLibraryInfo(const void *libPtr, DynLibInfo &lib)
return false;
}
baseAddr = reinterpret_cast<unsigned long>(info.AllocationBase);
baseAddr = reinterpret_cast<uintptr_t>(info.AllocationBase);
/* All this is for our insane sanity checks :o */
dos = reinterpret_cast<IMAGE_DOS_HEADER *>(baseAddr);
@ -322,7 +451,7 @@ bool MemoryUtils::GetLibraryInfo(const void *libPtr, DynLibInfo &lib)
}
/* This is for our insane sanity checks :o */
baseAddr = reinterpret_cast<unsigned long>(info.dli_fbase);
baseAddr = reinterpret_cast<uintptr_t>(info.dli_fbase);
file = reinterpret_cast<Elf32_Ehdr *>(baseAddr);
/* Check ELF magic */
@ -364,6 +493,59 @@ bool MemoryUtils::GetLibraryInfo(const void *libPtr, DynLibInfo &lib)
lib.memorySize += hdr.p_memsz;
}
}
#elif defined PLATFORM_APPLE
Dl_info info;
struct mach_header *file;
struct segment_command *seg;
uint32_t cmd_count;
if (!dladdr(libPtr, &info))
{
return false;
}
if (!info.dli_fbase || !info.dli_fname)
{
return false;
}
/* This is for our insane sanity checks :o */
baseAddr = (uintptr_t)info.dli_fbase;
file = (struct mach_header *)baseAddr;
/* Check Mach-O magic */
if (file->magic != MH_MAGIC)
{
return false;
}
/* Check architecture (32-bit/x86) */
if (file->cputype != CPU_TYPE_I386 || file->cpusubtype != CPU_SUBTYPE_I386_ALL)
{
return false;
}
/* For our purposes, this must be a dynamic library */
if (file->filetype != MH_DYLIB)
{
return false;
}
cmd_count = file->ncmds;
seg = (struct segment_command *)(baseAddr + sizeof(struct mach_header));
/* Add up memory sizes of mapped segments */
for (uint32_t i = 0; i < cmd_count; i++)
{
if (seg->cmd == LC_SEGMENT)
{
lib.memorySize += seg->vmsize;
}
seg = (struct segment_command *)((uintptr_t)seg + seg->cmdsize);
}
#endif

16
core/MemoryUtils.h
View File

@ -2,7 +2,7 @@
* vim: set ts=4 sw=4 tw=99 noet :
* =============================================================================
* SourceMod
* Copyright (C) 2004-2000 AlliedModders LLC. All rights reserved.
* Copyright (C) 2004-2010 AlliedModders LLC. All rights reserved.
* =============================================================================
*
* This program is free software; you can redistribute it and/or modify it under
@ -32,7 +32,7 @@
#include <IMemoryUtils.h>
#include "sm_globals.h"
#ifdef PLATFORM_LINUX
#if defined PLATFORM_LINUX || defined PLATFORM_APPLE
#include <sh_vector.h>
#include "sm_symtable.h"
@ -47,13 +47,11 @@ struct DynLibInfo
size_t memorySize;
};
#ifdef PLATFORM_LINUX
typedef uint32_t Elf32_Addr;
#if defined PLATFORM_LINUX || defined PLATFORM_APPLE
struct LibSymbolTable
{
SymbolTable table;
Elf32_Addr lib_base;
uintptr_t lib_base;
uint32_t last_pos;
};
#endif
@ -63,6 +61,7 @@ class MemoryUtils :
public SMGlobalClass
{
public:
MemoryUtils();
~MemoryUtils();
public: // SMGlobalClass
void OnSourceModAllInitialized();
@ -71,9 +70,12 @@ public: // IMemoryUtils
void *ResolveSymbol(void *handle, const char *symbol);
public:
bool GetLibraryInfo(const void *libPtr, DynLibInfo &lib);
#ifdef PLATFORM_LINUX
#if defined PLATFORM_LINUX || defined PLATFORM_APPLE
private:
CVector<LibSymbolTable *> m_SymTables;
#ifdef PLATFORM_APPLE
struct dyld_all_image_infos *m_ImageList;
#endif
#endif
};

9
public/IMemoryUtils.h
View File

@ -67,11 +67,14 @@ namespace SourceMod
/**
* @brief Retrieves a symbol pointer from a dynamic library.
*
* Note: On Linux, this function is able to resolve symbols that are hidden via GCC's
* -fvisibility=hidden option.
* Note: On Linux and Mac OS X, this function is able to resolve symbols that are hidden
* via GCC's -fvisibility=hidden option.
*
* Note: On Mac OS X, the symbol name should be passed without the prepended underscore,
* as this is how dlsym() would expect it.
*
* @param handle Operating system specific handle that points to dynamic library.
* This comes from dlopen() on Linux or LoadLibrary() on Windows.
* This comes from dlopen() on Linux/OS X or LoadLibrary() on Windows.
* @param symbol Symbol name.
* @return Symbol pointer, or NULL if not found.
*/