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 18 // Some of these functions aren't standard or if they conform, the name does not. 19 20 int asprintf(char **sptr, const char *__restrict format, ...) 21 { 22 va_list ap; 23 va_start(ap, format); 24 int result; 25 result = vasprintf(sptr, format, ap); 26 va_end(ap); 27 return result; 28 } 29 30 // Like sprintf, but when return value >= 0 it returns 31 // a pointer to a malloc'd string in *sptr. 32 // If return >= 0, use free to delete *sptr. 33 int vasprintf( char **sptr, const char *__restrict format, va_list ap ) 34 { 35 *sptr = NULL; 36 // Query the count required. 37 int count = _vsnprintf( NULL, 0, format, ap ); 38 if (count < 0) 39 return count; 40 size_t buffer_size = static_cast<size_t>(count) + 1; 41 char* p = static_cast<char*>(malloc(buffer_size)); 42 if ( ! p ) 43 return -1; 44 // If we haven't used exactly what was required, something is wrong. 45 // Maybe bug in vsnprintf. Report the error and return. 46 if (_vsnprintf(p, buffer_size, format, ap) != count) { 47 free(p); 48 return -1; 49 } 50 // All good. This is returning memory to the caller not freeing it. 51 *sptr = p; 52 return count; 53 } 54 55 // Returns >= 0: the number of wide characters found in the 56 // multi byte sequence src (of src_size_bytes), that fit in the buffer dst 57 // (of max_dest_chars elements size). The count returned excludes the 58 // null terminator. When dst is NULL, no characters are copied 59 // and no "out" parameters are updated. 60 // Returns (size_t) -1: an incomplete sequence encountered. 61 // Leaves *src pointing the next character to convert or NULL 62 // if a null character was converted from *src. 63 size_t mbsnrtowcs( wchar_t *__restrict dst, const char **__restrict src, 64 size_t src_size_bytes, size_t max_dest_chars, mbstate_t *__restrict ps ) 65 { 66 const size_t terminated_sequence = static_cast<size_t>(0); 67 //const size_t invalid_sequence = static_cast<size_t>(-1); 68 const size_t incomplete_sequence = static_cast< size_t>(-2); 69 70 size_t dest_converted = 0; 71 size_t source_converted = 0; 72 size_t source_remaining = src_size_bytes; 73 size_t result = 0; 74 bool have_result = false; 75 76 while ( source_remaining ) { 77 if ( dst && dest_converted >= max_dest_chars ) 78 break; 79 // Converts one multi byte character. 80 // if result > 0, it's the size in bytes of that character. 81 // othewise if result is zero it indicates the null character has been found. 82 // otherwise it's an error and errno may be set. 83 size_t char_size = mbrtowc( dst ? dst + dest_converted : NULL, *src + source_converted, source_remaining, ps ); 84 // Don't do anything to change errno from here on. 85 if ( char_size > 0 ) { 86 source_remaining -= char_size; 87 source_converted += char_size; 88 ++dest_converted; 89 continue; 90 } 91 result = char_size; 92 have_result = true; 93 break; 94 } 95 if ( dst ) { 96 if ( have_result && result == terminated_sequence ) 97 *src = NULL; 98 else 99 *src += source_converted; 100 } 101 if ( have_result && result != terminated_sequence && result != incomplete_sequence ) 102 return static_cast<size_t>(-1); 103 104 return dest_converted; 105 } 106 107 // Converts max_source_chars from the wide character buffer pointer to by *src, 108 // into the multi byte character sequence buffer stored at dst which must be 109 // dst_size_bytes bytes in size. 110 // Returns >= 0: the number of bytes in the sequence 111 // converted from *src, excluding the null terminator. 112 // Returns size_t(-1) if an error occurs, also sets errno. 113 // If dst is NULL dst_size_bytes is ignored and no bytes are copied to dst 114 // and no "out" parameters are updated. 115 size_t wcsnrtombs( char *__restrict dst, const wchar_t **__restrict src, 116 size_t max_source_chars, size_t dst_size_bytes, mbstate_t *__restrict ps ) 117 { 118 //const size_t invalid_sequence = static_cast<size_t>(-1); 119 120 size_t source_converted = 0; 121 size_t dest_converted = 0; 122 size_t dest_remaining = dst_size_bytes; 123 size_t char_size = 0; 124 const errno_t no_error = ( errno_t) 0; 125 errno_t result = ( errno_t ) 0; 126 bool have_result = false; 127 bool terminator_found = false; 128 129 while ( source_converted != max_source_chars ) { 130 if ( ! dest_remaining ) 131 break; 132 wchar_t c = (*src)[source_converted]; 133 if ( dst ) 134 result = wcrtomb_s( &char_size, dst + dest_converted, dest_remaining, c, ps); 135 else 136 result = wcrtomb_s( &char_size, NULL, 0, c, ps); 137 // If result is zero there is no error and char_size contains the 138 // size of the multi-byte-sequence converted. 139 // Otherwise result indicates an errno type error. 140 if ( result == no_error ) { 141 if ( c == L'\0' ) { 142 terminator_found = true; 143 break; 144 } 145 ++source_converted; 146 if ( dst ) 147 dest_remaining -= char_size; 148 dest_converted += char_size; 149 continue; 150 } 151 have_result = true; 152 break; 153 } 154 if ( dst ) { 155 if ( terminator_found ) 156 *src = NULL; 157 else 158 *src = *src + source_converted; 159 } 160 if ( have_result && result != no_error ) { 161 errno = result; 162 return static_cast<size_t>(-1); 163 } 164 165 return dest_converted; 166 } 167
