1 // Copyright (c) 2009, Google Inc. 2 // All rights reserved. 3 // 4 // Redistribution and use in source and binary forms, with or without 5 // modification, are permitted provided that the following conditions are 6 // met: 7 // 8 // * Redistributions of source code must retain the above copyright 9 // notice, this list of conditions and the following disclaimer. 10 // * Redistributions in binary form must reproduce the above 11 // copyright notice, this list of conditions and the following disclaimer 12 // in the documentation and/or other materials provided with the 13 // distribution. 14 // * Neither the name of Google Inc. nor the names of its 15 // contributors may be used to endorse or promote products derived from 16 // this software without specific prior written permission. 17 // 18 // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS 19 // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT 20 // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR 21 // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT 22 // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, 23 // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT 24 // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, 25 // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY 26 // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT 27 // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE 28 // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. 29 30 // This header provides replacements for libc functions that we need. We if 31 // call the libc functions directly we risk crashing in the dynamic linker as 32 // it tries to resolve uncached PLT entries. 33 34 #ifndef CLIENT_LINUX_LINUX_LIBC_SUPPORT_H_ 35 #define CLIENT_LINUX_LINUX_LIBC_SUPPORT_H_ 36 37 #include <stdint.h> 38 #include <limits.h> 39 #include <sys/types.h> 40 41 extern "C" { 42 43 extern size_t my_strlen(const char* s); 44 45 extern int my_strcmp(const char* a, const char* b); 46 47 extern int my_strncmp(const char* a, const char* b, size_t len); 48 49 // Parse a non-negative integer. 50 // result: (output) the resulting non-negative integer 51 // s: a NUL terminated string 52 // Return true iff successful. 53 extern bool my_strtoui(int* result, const char* s); 54 55 // Return the length of the given unsigned integer when expressed in base 10. 56 extern unsigned my_uint_len(uintmax_t i); 57 58 // Convert an unsigned integer to a string 59 // output: (output) the resulting string is written here. This buffer must be 60 // large enough to hold the resulting string. Call |my_uint_len| to get the 61 // required length. 62 // i: the unsigned integer to serialise. 63 // i_len: the length of the integer in base 10 (see |my_uint_len|). 64 extern void my_uitos(char* output, uintmax_t i, unsigned i_len); 65 66 extern const char* my_strchr(const char* haystack, char needle); 67 68 extern const char* my_strrchr(const char* haystack, char needle); 69 70 // Read a hex value 71 // result: (output) the resulting value 72 // s: a string 73 // Returns a pointer to the first invalid charactor. 74 extern const char* my_read_hex_ptr(uintptr_t* result, const char* s); 75 76 extern const char* my_read_decimal_ptr(uintptr_t* result, const char* s); 77 78 extern void my_memset(void* ip, char c, size_t len); 79 80 extern void* my_memchr(const void* src, int c, size_t len); 81 82 // The following are considered safe to use in a compromised environment. 83 // Besides, this gives the compiler an opportunity to optimize their calls. 84 #define my_memcpy memcpy 85 #define my_memmove memmove 86 #define my_memcmp memcmp 87 88 extern size_t my_strlcpy(char* s1, const char* s2, size_t len); 89 90 extern size_t my_strlcat(char* s1, const char* s2, size_t len); 91 92 extern int my_isspace(int ch); 93 94 } // extern "C" 95 96 #endif // CLIENT_LINUX_LINUX_LIBC_SUPPORT_H_ 97