| 1 | /*␊ |
| 2 | * Symbols.c␊ |
| 3 | * ␊ |
| 4 | * Module loader support module. This module is the first module to ever be loaded.␊ |
| 5 | * It contains a copy of each symbol inside ov the current version of chameleon as well ␊ |
| 6 | * as a strcmp function. Chameleon calls lookup_symbol to resolve internal symbols␊ |
| 7 | * when they are requested by a module. This module does *not* depend on any internal␊ |
| 8 | * symbols, as such it can be loaded without a symbol table initialized.␊ |
| 9 | *␊ |
| 10 | * Copyright (c) 2009 Evan Lojewski. All rights reserved.␊ |
| 11 | */␊ |
| 12 | ␊ |
| 13 | #include "Symbols.h"␊ |
| 14 | ␊ |
| 15 | static int strcmp(const char * s1, const char * s2);␊ |
| 16 | ␊ |
| 17 | void Symbols_start()␊ |
| 18 | {␊ |
| 19 | ␉// load_dependency("Symbols", 300);␊ |
| 20 | ␉//verbose("Symbols_start\n");␊ |
| 21 | }␊ |
| 22 | ␊ |
| 23 | unsigned int lookup_symbol(const char* symbol)␊ |
| 24 | {␊ |
| 25 | ␉if(strcmp(symbol, "dyld_stub_binder") == 0) return lookup_symbol("_dyld_stub_binder");␉// ugly hack␊ |
| 26 | ␉ ␊ |
| 27 | ␉int upperLimit = sizeof(symbolList) / sizeof(symbolList[0]) - 1;␉␉␊ |
| 28 | ␉int lowerLimit = 0;␊ |
| 29 | ␉int compareIndex = (upperLimit - lowerLimit) >> 1; // Midpoint␊ |
| 30 | ␉int result;␊ |
| 31 | ␉␊ |
| 32 | ␉while((result = strcmp(symbol, symbolList[compareIndex].symbol)) != 0)␊ |
| 33 | ␉{␊ |
| 34 | ␉␉if(result > 0)␉// We need to search a HIGHER index␊ |
| 35 | ␉␉{␊ |
| 36 | ␉␉␉if(compareIndex != lowerLimit)␊ |
| 37 | ␉␉␉{␊ |
| 38 | ␉␉␉␉lowerLimit = compareIndex;␊ |
| 39 | ␉␉␉}␊ |
| 40 | ␉␉␉else␊ |
| 41 | ␉␉␉{␊ |
| 42 | ␉␉␉␉return 0xFFFFFFFF;␉// Symbol not found␊ |
| 43 | ␉␉␉}␊ |
| 44 | ␉␉␉compareIndex = (upperLimit + lowerLimit + 1) >> 1;␉// Midpoint, round up␊ |
| 45 | ␉␉}␊ |
| 46 | ␉␉else // We Need to search a LOWER index␊ |
| 47 | ␉␉{␊ |
| 48 | ␉␉␉if(compareIndex != upperLimit)␊ |
| 49 | ␉␉␉{␊ |
| 50 | ␉␉␉␉upperLimit = compareIndex;␊ |
| 51 | ␉␉␉}␊ |
| 52 | ␉␉␉else␊ |
| 53 | ␉␉␉{␊ |
| 54 | ␉␉␉␉return 0xFFFFFFFF;␉// Symbol not found␊ |
| 55 | ␉␉␉}␊ |
| 56 | ␉␉␉compareIndex = (upperLimit + lowerLimit) >> 1;␉// Midpoint, round down␊ |
| 57 | ␉␉}␊ |
| 58 | ␉}␊ |
| 59 | ␉return symbolList[compareIndex].addr;␊ |
| 60 | }␊ |
| 61 | ␊ |
| 62 | /*␊ |
| 63 | * strcmp - Copied from libsa/string.c due to symbols not able to be resolved at this point␊ |
| 64 | */␊ |
| 65 | static int strcmp(const char * s1, const char * s2)␊ |
| 66 | {␊ |
| 67 | ␉while (*s1 && (*s1 == *s2)) {␊ |
| 68 | ␉␉s1++;␊ |
| 69 | ␉␉s2++;␊ |
| 70 | ␉}␊ |
| 71 | ␉return (*s1 - *s2);␊ |
| 72 | }␊ |
| 73 | ␊ |
| 74 | ␊ |
| 75 | ␊ |
| 76 | |
