| /***************************************************************************/ |
| /* */ |
| /* cf2stack.c */ |
| /* */ |
| /* Adobe's code for emulating a CFF stack (body). */ |
| /* */ |
| /* Copyright 2007-2013 Adobe Systems Incorporated. */ |
| /* */ |
| /* This software, and all works of authorship, whether in source or */ |
| /* object code form as indicated by the copyright notice(s) included */ |
| /* herein (collectively, the "Work") is made available, and may only be */ |
| /* used, modified, and distributed under the FreeType Project License, */ |
| /* LICENSE.TXT. Additionally, subject to the terms and conditions of the */ |
| /* FreeType Project License, each contributor to the Work hereby grants */ |
| /* to any individual or legal entity exercising permissions granted by */ |
| /* the FreeType Project License and this section (hereafter, "You" or */ |
| /* "Your") a perpetual, worldwide, non-exclusive, no-charge, */ |
| /* royalty-free, irrevocable (except as stated in this section) patent */ |
| /* license to make, have made, use, offer to sell, sell, import, and */ |
| /* otherwise transfer the Work, where such license applies only to those */ |
| /* patent claims licensable by such contributor that are necessarily */ |
| /* infringed by their contribution(s) alone or by combination of their */ |
| /* contribution(s) with the Work to which such contribution(s) was */ |
| /* submitted. If You institute patent litigation against any entity */ |
| /* (including a cross-claim or counterclaim in a lawsuit) alleging that */ |
| /* the Work or a contribution incorporated within the Work constitutes */ |
| /* direct or contributory patent infringement, then any patent licenses */ |
| /* granted to You under this License for that Work shall terminate as of */ |
| /* the date such litigation is filed. */ |
| /* */ |
| /* By using, modifying, or distributing the Work you indicate that you */ |
| /* have read and understood the terms and conditions of the */ |
| /* FreeType Project License as well as those provided in this section, */ |
| /* and you accept them fully. */ |
| /* */ |
| /***************************************************************************/ |
| |
| |
| #include "cf2ft.h" |
| #include FT_INTERNAL_DEBUG_H |
| |
| #include "cf2glue.h" |
| #include "cf2font.h" |
| #include "cf2stack.h" |
| |
| #include "cf2error.h" |
| |
| |
| /* Allocate and initialize an instance of CF2_Stack. */ |
| /* Note: This function returns NULL on error (does not set */ |
| /* `error'). */ |
| FT_LOCAL_DEF( CF2_Stack ) |
| cf2_stack_init( FT_Memory memory, |
| FT_Error* e ) |
| { |
| FT_Error error = FT_Err_Ok; /* for FT_NEW */ |
| |
| CF2_Stack stack = NULL; |
| |
| |
| if ( !FT_NEW( stack ) ) |
| { |
| /* initialize the structure; FT_NEW zeroes it */ |
| stack->memory = memory; |
| stack->error = e; |
| stack->top = &stack->buffer[0]; /* empty stack */ |
| } |
| |
| return stack; |
| } |
| |
| |
| FT_LOCAL_DEF( void ) |
| cf2_stack_free( CF2_Stack stack ) |
| { |
| if ( stack ) |
| { |
| FT_Memory memory = stack->memory; |
| |
| |
| /* free the main structure */ |
| FT_FREE( stack ); |
| } |
| } |
| |
| |
| FT_LOCAL_DEF( CF2_UInt ) |
| cf2_stack_count( CF2_Stack stack ) |
| { |
| return (CF2_UInt)( stack->top - &stack->buffer[0] ); |
| } |
| |
| |
| FT_LOCAL_DEF( void ) |
| cf2_stack_pushInt( CF2_Stack stack, |
| CF2_Int val ) |
| { |
| if ( stack->top == &stack->buffer[CF2_OPERAND_STACK_SIZE] ) |
| { |
| CF2_SET_ERROR( stack->error, Stack_Overflow ); |
| return; /* stack overflow */ |
| } |
| |
| stack->top->u.i = val; |
| stack->top->type = CF2_NumberInt; |
| ++stack->top; |
| } |
| |
| |
| FT_LOCAL_DEF( void ) |
| cf2_stack_pushFixed( CF2_Stack stack, |
| CF2_Fixed val ) |
| { |
| if ( stack->top == &stack->buffer[CF2_OPERAND_STACK_SIZE] ) |
| { |
| CF2_SET_ERROR( stack->error, Stack_Overflow ); |
| return; /* stack overflow */ |
| } |
| |
| stack->top->u.r = val; |
| stack->top->type = CF2_NumberFixed; |
| ++stack->top; |
| } |
| |
| |
| /* this function is only allowed to pop an integer type */ |
| FT_LOCAL_DEF( CF2_Int ) |
| cf2_stack_popInt( CF2_Stack stack ) |
| { |
| if ( stack->top == &stack->buffer[0] ) |
| { |
| CF2_SET_ERROR( stack->error, Stack_Underflow ); |
| return 0; /* underflow */ |
| } |
| if ( stack->top[-1].type != CF2_NumberInt ) |
| { |
| CF2_SET_ERROR( stack->error, Syntax_Error ); |
| return 0; /* type mismatch */ |
| } |
| |
| --stack->top; |
| |
| return stack->top->u.i; |
| } |
| |
| |
| /* Note: type mismatch is silently cast */ |
| /* TODO: check this */ |
| FT_LOCAL_DEF( CF2_Fixed ) |
| cf2_stack_popFixed( CF2_Stack stack ) |
| { |
| if ( stack->top == &stack->buffer[0] ) |
| { |
| CF2_SET_ERROR( stack->error, Stack_Underflow ); |
| return cf2_intToFixed( 0 ); /* underflow */ |
| } |
| |
| --stack->top; |
| |
| switch ( stack->top->type ) |
| { |
| case CF2_NumberInt: |
| return cf2_intToFixed( stack->top->u.i ); |
| case CF2_NumberFrac: |
| return cf2_fracToFixed( stack->top->u.f ); |
| default: |
| return stack->top->u.r; |
| } |
| } |
| |
| |
| /* Note: type mismatch is silently cast */ |
| /* TODO: check this */ |
| FT_LOCAL_DEF( CF2_Fixed ) |
| cf2_stack_getReal( CF2_Stack stack, |
| CF2_UInt idx ) |
| { |
| FT_ASSERT( cf2_stack_count( stack ) <= CF2_OPERAND_STACK_SIZE ); |
| |
| if ( idx >= cf2_stack_count( stack ) ) |
| { |
| CF2_SET_ERROR( stack->error, Stack_Overflow ); |
| return cf2_intToFixed( 0 ); /* bounds error */ |
| } |
| |
| switch ( stack->buffer[idx].type ) |
| { |
| case CF2_NumberInt: |
| return cf2_intToFixed( stack->buffer[idx].u.i ); |
| case CF2_NumberFrac: |
| return cf2_fracToFixed( stack->buffer[idx].u.f ); |
| default: |
| return stack->buffer[idx].u.r; |
| } |
| } |
| |
| |
| FT_LOCAL( void ) |
| cf2_stack_roll( CF2_Stack stack, |
| CF2_Int count, |
| CF2_Int shift ) |
| { |
| /* we initialize this variable to avoid compiler warnings */ |
| CF2_StackNumber last = { { 0 }, CF2_NumberInt }; |
| |
| CF2_Int start_idx, idx, i; |
| |
| |
| if ( count < 2 ) |
| return; /* nothing to do (values 0 and 1), or undefined value */ |
| |
| if ( (CF2_UInt)count > cf2_stack_count( stack ) ) |
| { |
| CF2_SET_ERROR( stack->error, Stack_Overflow ); |
| return; |
| } |
| |
| if ( shift < 0 ) |
| shift = -( ( -shift ) % count ); |
| else |
| shift %= count; |
| |
| if ( shift == 0 ) |
| return; /* nothing to do */ |
| |
| /* We use the following algorithm to do the rolling, */ |
| /* which needs two temporary variables only. */ |
| /* */ |
| /* Example: */ |
| /* */ |
| /* count = 8 */ |
| /* shift = 2 */ |
| /* */ |
| /* stack indices before roll: 7 6 5 4 3 2 1 0 */ |
| /* stack indices after roll: 1 0 7 6 5 4 3 2 */ |
| /* */ |
| /* The value of index 0 gets moved to index 2, while */ |
| /* the old value of index 2 gets moved to index 4, */ |
| /* and so on. We thus have the following copying */ |
| /* chains for shift value 2. */ |
| /* */ |
| /* 0 -> 2 -> 4 -> 6 -> 0 */ |
| /* 1 -> 3 -> 5 -> 7 -> 1 */ |
| /* */ |
| /* If `count' and `shift' are incommensurable, we */ |
| /* have a single chain only. Otherwise, increase */ |
| /* the start index by 1 after the first chain, then */ |
| /* do the next chain until all elements in all */ |
| /* chains are handled. */ |
| |
| start_idx = -1; |
| idx = -1; |
| for ( i = 0; i < count; i++ ) |
| { |
| CF2_StackNumber tmp; |
| |
| |
| if ( start_idx == idx ) |
| { |
| start_idx++; |
| idx = start_idx; |
| last = stack->buffer[idx]; |
| } |
| |
| idx += shift; |
| if ( idx >= count ) |
| idx -= count; |
| else if ( idx < 0 ) |
| idx += count; |
| |
| tmp = stack->buffer[idx]; |
| stack->buffer[idx] = last; |
| last = tmp; |
| } |
| } |
| |
| |
| FT_LOCAL_DEF( void ) |
| cf2_stack_clear( CF2_Stack stack ) |
| { |
| stack->top = &stack->buffer[0]; |
| } |
| |
| |
| /* END */ |
