1 /***************************************************************************/
2 /*                                                                         */
3 /*  cf2stack.c                                                             */
4 /*                                                                         */
5 /*    Adobe's code for emulating a CFF stack (body).                       */
6 /*                                                                         */
7 /*  Copyright 2007-2013 Adobe Systems Incorporated.                        */
8 /*                                                                         */
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35 /*                                                                         */
36 /***************************************************************************/
37 
38 
39 #include "cf2ft.h"
40 #include FT_INTERNAL_DEBUG_H
41 
42 #include "cf2glue.h"
43 #include "cf2font.h"
44 #include "cf2stack.h"
45 
46 #include "cf2error.h"
47 
48 
49   /* Allocate and initialize an instance of CF2_Stack.       */
50   /* Note: This function returns NULL on error (does not set */
51   /* `error').                                               */
52   FT_LOCAL_DEF( CF2_Stack )
cf2_stack_init(FT_Memory memory,FT_Error * e)53   cf2_stack_init( FT_Memory  memory,
54                   FT_Error*  e )
55   {
56     FT_Error  error = FT_Err_Ok;     /* for FT_QNEW */
57 
58     CF2_Stack  stack = NULL;
59 
60 
61     if ( !FT_QNEW( stack ) )
62     {
63       /* initialize the structure; FT_QNEW zeroes it */
64       stack->memory = memory;
65       stack->error  = e;
66       stack->top    = &stack->buffer[0]; /* empty stack */
67     }
68 
69     return stack;
70   }
71 
72 
73   FT_LOCAL_DEF( void )
cf2_stack_free(CF2_Stack stack)74   cf2_stack_free( CF2_Stack  stack )
75   {
76     if ( stack )
77     {
78       FT_Memory  memory = stack->memory;
79 
80 
81       /* free the main structure */
82       FT_FREE( stack );
83     }
84   }
85 
86 
87   FT_LOCAL_DEF( CF2_UInt )
cf2_stack_count(CF2_Stack stack)88   cf2_stack_count( CF2_Stack  stack )
89   {
90     return (CF2_UInt)( stack->top - &stack->buffer[0] );
91   }
92 
93 
94   FT_LOCAL_DEF( void )
cf2_stack_pushInt(CF2_Stack stack,CF2_Int val)95   cf2_stack_pushInt( CF2_Stack  stack,
96                      CF2_Int    val )
97   {
98     if ( stack->top == &stack->buffer[CF2_OPERAND_STACK_SIZE] )
99     {
100       CF2_SET_ERROR( stack->error, Stack_Overflow );
101       return;     /* stack overflow */
102     }
103 
104     stack->top->u.i  = val;
105     stack->top->type = CF2_NumberInt;
106     ++stack->top;
107   }
108 
109 
110   FT_LOCAL_DEF( void )
cf2_stack_pushFixed(CF2_Stack stack,CF2_Fixed val)111   cf2_stack_pushFixed( CF2_Stack  stack,
112                        CF2_Fixed  val )
113   {
114     if ( stack->top == &stack->buffer[CF2_OPERAND_STACK_SIZE] )
115     {
116       CF2_SET_ERROR( stack->error, Stack_Overflow );
117       return;     /* stack overflow */
118     }
119 
120     stack->top->u.r  = val;
121     stack->top->type = CF2_NumberFixed;
122     ++stack->top;
123   }
124 
125 
126   /* this function is only allowed to pop an integer type */
127   FT_LOCAL_DEF( CF2_Int )
cf2_stack_popInt(CF2_Stack stack)128   cf2_stack_popInt( CF2_Stack  stack )
129   {
130     if ( stack->top == &stack->buffer[0] )
131     {
132       CF2_SET_ERROR( stack->error, Stack_Underflow );
133       return 0;   /* underflow */
134     }
135     if ( stack->top[-1].type != CF2_NumberInt )
136     {
137       CF2_SET_ERROR( stack->error, Syntax_Error );
138       return 0;   /* type mismatch */
139     }
140 
141     --stack->top;
142 
143     return stack->top->u.i;
144   }
145 
146 
147   /* Note: type mismatch is silently cast */
148   /* TODO: check this */
149   FT_LOCAL_DEF( CF2_Fixed )
cf2_stack_popFixed(CF2_Stack stack)150   cf2_stack_popFixed( CF2_Stack  stack )
151   {
152     if ( stack->top == &stack->buffer[0] )
153     {
154       CF2_SET_ERROR( stack->error, Stack_Underflow );
155       return cf2_intToFixed( 0 );    /* underflow */
156     }
157 
158     --stack->top;
159 
160     switch ( stack->top->type )
161     {
162     case CF2_NumberInt:
163       return cf2_intToFixed( stack->top->u.i );
164     case CF2_NumberFrac:
165       return cf2_fracToFixed( stack->top->u.f );
166     default:
167       return stack->top->u.r;
168     }
169   }
170 
171 
172   /* Note: type mismatch is silently cast */
173   /* TODO: check this */
174   FT_LOCAL_DEF( CF2_Fixed )
cf2_stack_getReal(CF2_Stack stack,CF2_UInt idx)175   cf2_stack_getReal( CF2_Stack  stack,
176                      CF2_UInt   idx )
177   {
178     FT_ASSERT( cf2_stack_count( stack ) <= CF2_OPERAND_STACK_SIZE );
179 
180     if ( idx >= cf2_stack_count( stack ) )
181     {
182       CF2_SET_ERROR( stack->error, Stack_Overflow );
183       return cf2_intToFixed( 0 );    /* bounds error */
184     }
185 
186     switch ( stack->buffer[idx].type )
187     {
188     case CF2_NumberInt:
189       return cf2_intToFixed( stack->buffer[idx].u.i );
190     case CF2_NumberFrac:
191       return cf2_fracToFixed( stack->buffer[idx].u.f );
192     default:
193       return stack->buffer[idx].u.r;
194     }
195   }
196 
197 
198   FT_LOCAL_DEF( void )
cf2_stack_clear(CF2_Stack stack)199   cf2_stack_clear( CF2_Stack  stack )
200   {
201     stack->top = &stack->buffer[0];
202   }
203 
204 
205 /* END */
206