1 // -*- C++ -*- 2 //===----------------------- support/win32/support.h ----------------------===// 3 // 4 // The LLVM Compiler Infrastructure 5 // 6 // This file is dual licensed under the MIT and the University of Illinois Open 7 // Source Licenses. See LICENSE.TXT for details. 8 // 9 //===----------------------------------------------------------------------===// 10 11 #include <cstdarg> // va_start, va_end 12 #include <cstddef> // size_t 13 #include <cstdlib> // malloc 14 #include <cstdio> // vsprintf, vsnprintf 15 #include <cstring> // strcpy, wcsncpy 16 #include <cwchar> // mbstate_t 17 #include <memory> // unique_ptr 18 19 namespace { // Private 20 21 struct free_deleter { 22 inline void operator()(char* p) { free(p); } 23 }; 24 } 25 // Some of these functions aren't standard or if they conform, the name does not. 26 27 int asprintf(char **sptr, const char *__restrict format, ...) 28 { 29 va_list ap; 30 va_start(ap, format); 31 int result; 32 #ifndef _LIBCPP_NO_EXCEPTIONS 33 try { 34 #endif 35 result = vasprintf(sptr, format, ap); 36 #ifndef _LIBCPP_NO_EXCEPTIONS 37 } catch( ... ) { 38 va_end(ap); 39 throw; 40 } 41 #endif 42 va_end(ap); 43 return result; 44 } 45 46 // Like sprintf, but when return value >= 0 it returns a pointer to a malloc'd string in *sptr. 47 // If return >= 0, use free to delete *sptr. 48 int vasprintf( char **sptr, const char *__restrict format, va_list ap ) 49 { 50 *sptr = NULL; 51 int count = _vsnprintf( NULL, 0, format, ap ); // Query the buffer size required. 52 if( count >= 0 ) { 53 std::unique_ptr<char, free_deleter> p( static_cast<char*>(malloc(count+1)) ); 54 if ( ! p ) 55 return -1; 56 if ( vsnprintf( p.get(), count+1, format, ap ) == count ) // We should have used exactly what was required. 57 *sptr = p.release(); 58 else // Otherwise something is wrong, likely a bug in vsnprintf. If so free the memory and report the error. 59 return -1; // Pointer will get automaticlaly deleted. 60 } 61 62 return count; 63 } 64 65 // Returns >= 0: the number of wide characters found in the multi byte sequence src (of src_size_bytes), 66 // that fit in the buffer dst (of max_dest_chars elements size). The count returned excludes the null terminator. 67 // When dst is NULL, no characters are copied and no "out" parameters are updated. 68 // Returns (size_t) -1: an incomplete sequence encountered. 69 // Leaves *src pointing the next character to convert or NULL if a null character was converted from *src. 70 size_t mbsnrtowcs( wchar_t *__restrict dst, const char **__restrict src, 71 size_t src_size_bytes, size_t max_dest_chars, mbstate_t *__restrict ps ) 72 { 73 const size_t terminated_sequence = static_cast<size_t>(0); 74 //const size_t invalid_sequence = static_cast<size_t>(-1); 75 const size_t incomplete_sequence = static_cast< size_t>(-2); 76 77 size_t dest_converted = 0; 78 size_t source_converted = 0; 79 size_t source_remaining = src_size_bytes; 80 size_t result = 0; 81 bool have_result = false; 82 83 while ( source_remaining ) { 84 if ( dst && dest_converted >= max_dest_chars ) 85 break; 86 // Converts one multi byte character. 87 // if result > 0, it's the size in bytes of that character. 88 // othewise if result is zero it indicates the null character has been found. 89 // otherwise it's an error and errno may be set. 90 size_t char_size = mbrtowc( dst ? dst + dest_converted : NULL, *src + source_converted, source_remaining, ps ); 91 // Don't do anything to change errno from here on. 92 if ( char_size > 0 ) { 93 source_remaining -= char_size; 94 source_converted += char_size; 95 ++dest_converted; 96 continue; 97 } 98 result = char_size; 99 have_result = true; 100 break; 101 } 102 if ( dst ) { 103 if ( have_result && result == terminated_sequence ) 104 *src = NULL; 105 else 106 *src += source_converted; 107 } 108 if ( have_result && result != terminated_sequence && result != incomplete_sequence ) 109 return static_cast<size_t>(-1); 110 111 return dest_converted; 112 } 113 114 // Converts max_source_chars from the wide character buffer pointer to by *src, 115 // into the multi byte character sequence buffer stored at dst which must be dst_size_bytes bytes in size. 116 // Returns >= 0: the number of bytes in the sequence sequence converted frome *src, excluding the null terminator. 117 // Returns size_t(-1) if an error occurs, also sets errno. 118 // If dst is NULL dst_size_bytes is ignored and no bytes are copied to dst and no "out" parameters are updated. 119 size_t wcsnrtombs( char *__restrict dst, const wchar_t **__restrict src, 120 size_t max_source_chars, size_t dst_size_bytes, mbstate_t *__restrict ps ) 121 { 122 //const size_t invalid_sequence = static_cast<size_t>(-1); 123 124 size_t source_converted = 0; 125 size_t dest_converted = 0; 126 size_t dest_remaining = dst_size_bytes; 127 size_t char_size = 0; 128 const errno_t no_error = ( errno_t) 0; 129 errno_t result = ( errno_t ) 0; 130 bool have_result = false; 131 bool terminator_found = false; 132 133 while ( source_converted != max_source_chars ) { 134 if ( ! dest_remaining ) 135 break; 136 wchar_t c = (*src)[source_converted]; 137 if ( dst ) 138 result = wcrtomb_s( &char_size, dst + dest_converted, dest_remaining, c, ps); 139 else 140 result = wcrtomb_s( &char_size, NULL, 0, c, ps); 141 // If result is zero there is no error and char_size contains the size of the multi-byte-sequence converted. 142 // Otherwise result indicates an errno type error. 143 if ( result == no_error ) { 144 if ( c == L'\0' ) { 145 terminator_found = true; 146 break; 147 } 148 ++source_converted; 149 if ( dst ) 150 dest_remaining -= char_size; 151 dest_converted += char_size; 152 continue; 153 } 154 have_result = true; 155 break; 156 } 157 if ( dst ) { 158 if ( terminator_found ) 159 *src = NULL; 160 else 161 *src = *src + source_converted; 162 } 163 if ( have_result && result != no_error ) { 164 errno = result; 165 return static_cast<size_t>(-1); 166 } 167 168 return dest_converted; 169 } 170