ref: 11187206791326f7e851b62e13107723ce2c6505
dir: /src/base/ftstream.c/
#include <freetype/internal/ftstream.h> #include <freetype/internal/ftdebug.h> #undef FT_COMPONENT #define FT_COMPONENT trace_stream BASE_FUNC(void) FT_New_Memory_Stream( FT_Library library, void* base, unsigned long size, FT_Stream stream ) { stream->memory = library->memory; stream->base = (char*)base; stream->size = size; stream->pos = 0; stream->cursor = 0; stream->read = 0; stream->close = 0; } BASE_FUNC(FT_Error) FT_Seek_Stream( FT_Stream stream, FT_ULong pos ) { FT_Error error; stream->pos = pos; if (stream->read) { if (stream->read( stream, pos, 0, 0 )) { error = FT_Err_Invalid_Stream_Operation; FT_ERROR(( "FT_Seek_Stream:" )); FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx\n", pos, stream->size )); } else error = FT_Err_Ok; } /* note that seeking to the first position after the file is valid */ else if (pos > stream->size) { error = FT_Err_Invalid_Stream_Operation; FT_ERROR(( "FT_Seek_Stream:" )); FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx\n", pos, stream->size )); } else error = FT_Err_Ok; return error; } BASE_FUNC(FT_Error) FT_Skip_Stream( FT_Stream stream, FT_Long distance ) { return FT_Seek_Stream( stream, (FT_ULong)(stream->pos + distance) ); } BASE_FUNC(FT_Long) FT_Stream_Pos( FT_Stream stream ) { return stream->pos; } BASE_FUNC(FT_Error) FT_Read_Stream( FT_Stream stream, void* buffer, FT_ULong count ) { return FT_Read_Stream_At( stream, stream->pos, buffer, count ); } BASE_FUNC(FT_Error) FT_Read_Stream_At( FT_Stream stream, FT_ULong pos, void* buffer, FT_ULong count ) { FT_Error error = FT_Err_Ok; FT_ULong read_bytes; if (pos >= stream->size) { FT_ERROR(( "FT_Read_Stream_At:" )); FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx\n", pos, stream->size )); return FT_Err_Invalid_Stream_Operation; } if (stream->read) read_bytes = stream->read( stream, pos, buffer, count ); else { read_bytes = stream->size - pos; if (read_bytes > count) read_bytes = count; MEM_Copy( buffer, stream->base + pos, read_bytes ); } stream->pos = pos + read_bytes; if (read_bytes < count) { FT_ERROR(( "FT_Read_Stream_At:" )); FT_ERROR(( " invalid read, expected %lu bytes, got %lu", count, read_bytes )); error = FT_Err_Invalid_Stream_Operation; } return error; } BASE_FUNC(FT_Error) FT_Access_Frame( FT_Stream stream, FT_ULong count ) { FT_Error error = FT_Err_Ok; FT_ULong read_bytes; /* check for nested frame access */ FT_Assert( stream && stream->cursor == 0 ); if (stream->read) { /* allocate the frame in memory */ FT_Memory memory = stream->memory; if ( ALLOC( stream->base, count ) ) goto Exit; /* read it */ read_bytes = stream->read( stream, stream->pos, stream->base, count ); if (read_bytes < count) { FT_ERROR(( "FT_Access_Frame:" )); FT_ERROR(( " invalid read, expected %lu bytes, got %lu", count, read_bytes )); FREE( stream->base ); error = FT_Err_Invalid_Stream_Operation; } stream->cursor = stream->base; stream->limit = stream->cursor + count; stream->pos += read_bytes; } else { /* check current and new position */ if (stream->pos >= stream->size || stream->pos + count > stream->size) { FT_ERROR(( "FT_Access_Frame:" )); FT_ERROR(( " invalid i/o, pos = 0x%lx, count = %lu, size = 0x%lx", stream->pos, count, stream->size )); error = FT_Err_Invalid_Stream_Operation; goto Exit; } /* set cursor */ stream->cursor = stream->base + stream->pos; stream->limit = stream->cursor + count; stream->pos += count; } Exit: return error; } BASE_FUNC(void) FT_Forget_Frame( FT_Stream stream ) { /* IMPORTANT: The assertion stream->cursor != 0 was removed, given */ /* that it is possible to access a frame of length 0 in */ /* some weird fonts (usually, when accessing an array of */ /* 0 records, like in some strange kern tables).. */ /* */ /* In this case, the loader code handles the 0-length table */ /* gracefully, however, stream.cursor is really set to 0 by the */ /* FT_Access_Frame call, and this is not an error.. */ /* */ FT_Assert( stream ); if (stream->read) { FT_Memory memory = stream->memory; FREE( stream->base ); } stream->cursor = 0; stream->limit = 0; } BASE_FUNC(FT_Char) FT_Get_Char( FT_Stream stream ) { FT_Char result; FT_Assert( stream && stream->cursor ); result = 0; if (stream->cursor < stream->limit) result = *stream->cursor++; return result; } BASE_FUNC(FT_Short) FT_Get_Short( FT_Stream stream ) { char* p; FT_Short result; FT_Assert( stream && stream->cursor ); result = 0; p = stream->cursor; if (p+1 < stream->limit) result = NEXT_Short(p); stream->cursor = p; return result; } BASE_FUNC(FT_Long) FT_Get_Offset( FT_Stream stream ) { char* p; FT_Long result; FT_Assert( stream && stream->cursor ); result = 0; p = stream->cursor; if (p+2 < stream->limit) result = NEXT_Offset(p); stream->cursor = p; return result; } BASE_FUNC(FT_Long) FT_Get_Long( FT_Stream stream ) { char* p; FT_Long result; FT_Assert( stream && stream->cursor ); result = 0; p = stream->cursor; if (p+3 < stream->limit) result = NEXT_Long(p); stream->cursor = p; return result; } BASE_FUNC(FT_Char) FT_Read_Char( FT_Stream stream, FT_Error* error ) { char result = 0; FT_Assert( stream ); *error = FT_Err_Ok; if (stream->read) { if ( stream->read( stream, stream->pos, &result, 1L ) != 1L ) goto Fail; } else { if (stream->pos < stream->size) result = stream->base[stream->pos]; else goto Fail; } stream->pos++; return result; Fail: *error = FT_Err_Invalid_Stream_Operation; FT_ERROR(( "FT_Read_Char:" )); FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx", stream->pos, stream->size )); return 0; } BASE_FUNC(FT_Short) FT_Read_Short( FT_Stream stream, FT_Error* error ) { char reads[2]; char* p = 0; FT_Short result = 0; FT_Assert( stream ); *error = FT_Err_Ok; if (stream->pos+1 < stream->size) { if (stream->read) { if (stream->read( stream, stream->pos, reads, 2L ) != 2L ) goto Fail; p = reads; } else { p = stream->base + stream->pos; } if (p) result = NEXT_Short(p); } else goto Fail; stream->pos += 2; return result; Fail: *error = FT_Err_Invalid_Stream_Operation; FT_ERROR(( "FT_Read_Short:" )); FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx", stream->pos, stream->size )); return 0; } BASE_FUNC(FT_Long) FT_Read_Offset( FT_Stream stream, FT_Error* error ) { char reads[3]; char* p = 0; FT_Long result = 0; FT_Assert( stream ); *error = FT_Err_Ok; if (stream->pos+2 < stream->size) { if (stream->read) { if (stream->read( stream, stream->pos, reads, 3L ) != 3L ) goto Fail; p = reads; } else { p = stream->base + stream->pos; } if (p) result = NEXT_Offset(p); } else goto Fail; stream->pos += 3; return result; Fail: *error = FT_Err_Invalid_Stream_Operation; FT_ERROR(( "FT_Read_Offset:" )); FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx", stream->pos, stream->size )); return 0; } BASE_FUNC(FT_Long) FT_Read_Long( FT_Stream stream, FT_Error* error ) { char reads[4]; char* p = 0; FT_Long result = 0; FT_Assert( stream ); *error = FT_Err_Ok; if (stream->pos+3 < stream->size) { if (stream->read) { if (stream->read( stream, stream->pos, reads, 4L ) != 4L ) goto Fail; p = reads; } else { p = stream->base + stream->pos; } if (p) result = NEXT_Long(p); } else goto Fail; stream->pos += 4; return result; Fail: *error = FT_Err_Invalid_Stream_Operation; FT_ERROR(( "FT_Read_Long:" )); FT_ERROR(( " invalid i/o, pos = 0x%lx, size = 0x%lx", stream->pos, stream->size )); return 0; } BASE_FUNC(FT_Error) FT_Read_Fields( FT_Stream stream, const FT_Frame_Field* fields, void* structure ) { FT_Error error; FT_Bool frame_accessed = 0; if (!fields || !stream) return FT_Err_Invalid_Argument; error = FT_Err_Ok; do { FT_ULong value; FT_Int sign_shift; FT_Byte* p; switch (fields->value) { case ft_frame_start: /* access a new frame */ { error = FT_Access_Frame( stream, fields->offset ); if (error) goto Exit; frame_accessed = 1; fields++; continue; /* loop ! */ } case ft_frame_byte: case ft_frame_schar: /* read a single byte */ { value = GET_Byte(); sign_shift = 24; break; } case ft_frame_short_be: case ft_frame_ushort_be: /* read a 2-byte big-endian short */ { value = GET_UShort(); sign_shift = 16; break; } case ft_frame_short_le: case ft_frame_ushort_le: /* read a 2-byte little-endian short */ { char* p; value = 0; p = stream->cursor; if (p+1 < stream->limit) { value = (FT_UShort)p[0] | ((FT_UShort)p[1] << 8); stream->cursor += 2; } sign_shift = 16; break; } case ft_frame_long_be: case ft_frame_ulong_be: /* read a 4-byte big-endian long */ { value = GET_ULong(); sign_shift = 0; break; } case ft_frame_long_le: case ft_frame_ulong_le: /* read a 4-byte little-endian long */ { char* p; value = 0; p = stream->cursor; if (p+3 < stream->limit) { value = (FT_ULong)p[0] | ((FT_ULong)p[1] << 8) | ((FT_ULong)p[2] << 16) | ((FT_ULong)p[3] << 24); stream->cursor += 4; } sign_shift = 0; break; } case ft_frame_off3_be: case ft_frame_uoff3_be: /* read a 3-byte big-endian long */ { value = GET_UOffset(); sign_shift = 8; break; } case ft_frame_off3_le: case ft_frame_uoff3_le: /* read a 3-byte little-endian long */ { char* p; value = 0; p = stream->cursor; if (p+3 < stream->limit) { value = (FT_ULong)p[0] | ((FT_ULong)p[1] << 8) | ((FT_ULong)p[2] << 16) | ((FT_ULong)p[3] << 24); stream->cursor += 4; } sign_shift = 8; break; } default: /* otherwise, exit the loop */ goto Exit; } /* now, compute the signed value is necessary */ if (fields->value & FT_FRAME_OP_SIGNED) value = (FT_ULong)((FT_Long)(value << sign_shift) >> sign_shift); /* finally, store the value in the object */ p = (FT_Byte*)structure + fields->offset; switch (fields->size) { case 1: *(FT_Byte*)p = (FT_Byte) value; break; case 2: *(FT_UShort*)p = (FT_UShort)value; break; case 4: *(FT_ULong*)p = (FT_ULong) value; break; default: ; /* ignore !! */ } /* go to next field */ fields++; } while (1); Exit: /* close the frame if it was opened by this read */ if (frame_accessed) FT_Forget_Frame(stream); return error; }