1 /*
2  * This file is part of ltrace.
3  * Copyright (C) 2011,2012,2013 Petr Machata, Red Hat Inc.
4  * Copyright (C) 1997-2009 Juan Cespedes
5  *
6  * This program is free software; you can redistribute it and/or
7  * modify it under the terms of the GNU General Public License as
8  * published by the Free Software Foundation; either version 2 of the
9  * License, or (at your option) any later version.
10  *
11  * This program is distributed in the hope that it will be useful, but
12  * WITHOUT ANY WARRANTY; without even the implied warranty of
13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
14  * General Public License for more details.
15  *
16  * You should have received a copy of the GNU General Public License
17  * along with this program; if not, write to the Free Software
18  * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA
19  * 02110-1301 USA
20  */
21 
22 #ifndef TYPE_H
23 #define TYPE_H
24 
25 #include <stddef.h>
26 #include "forward.h"
27 #include "vect.h"
28 
29 enum arg_type {
30 	ARGTYPE_VOID,
31 	ARGTYPE_INT,
32 	ARGTYPE_UINT,
33 	ARGTYPE_LONG,
34 	ARGTYPE_ULONG,
35 	ARGTYPE_CHAR,
36 	ARGTYPE_SHORT,
37 	ARGTYPE_USHORT,
38 	ARGTYPE_FLOAT,
39 	ARGTYPE_DOUBLE,
40 	ARGTYPE_ARRAY,		/* Series of values in memory */
41 	ARGTYPE_STRUCT,		/* Structure of values */
42 	ARGTYPE_POINTER,	/* Pointer to some other type */
43 };
44 
45 struct arg_type_info {
46 	enum arg_type type;
47 	union {
48 		struct vect entries;
49 
50 		/* ARGTYPE_ARRAY */
51 		struct {
52 			struct arg_type_info *elt_type;
53 			struct expr_node *length;
54 			int own_info:1;
55 			int own_length:1;
56 		} array_info;
57 
58 		/* ARGTYPE_POINTER */
59 		struct {
60 			struct arg_type_info *info;
61 			int own_info:1;
62 		} ptr_info;
63 	} u;
64 
65 	struct lens *lens;
66 	int own_lens;
67 };
68 
69 /* Return a type info for simple type TYPE (which shall not be array,
70  * struct, or pointer.  Each call with the same TYPE yields the same
71  * arg_type_info pointer.  */
72 struct arg_type_info *type_get_simple(enum arg_type type);
73 struct arg_type_info *type_get_voidptr(void);
74 
75 /* Initialize INFO so it becomes ARGTYPE_STRUCT.  The created
76  * structure contains no fields.  Use type_struct_add to populate the
77  * structure.  */
78 void type_init_struct(struct arg_type_info *info);
79 
80 /* Add a new field of type FIELD_INFO to a structure INFO.  If OWN,
81  * the field type is owned and destroyed together with INFO.  */
82 int type_struct_add(struct arg_type_info *info,
83 		    struct arg_type_info *field_info, int own);
84 
85 /* Get IDX-th field of structure type INFO.  */
86 struct arg_type_info *type_struct_get(struct arg_type_info *info, size_t idx);
87 
88 /* Return number of fields of structure type INFO.  */
89 size_t type_struct_size(struct arg_type_info *info);
90 
91 /* Return number of elements of an aggregate type INFO.  This can be
92  * either ARGTYPE_STRUCT or ARGTYPE_ARRAY of constant length.  If
93  * ARGTYPE_ARRAY does not have a constant length, this returns -1.  */
94 size_t type_aggregate_size(struct arg_type_info *info);
95 
96 /* Initialize INFO so it becomes ARGTYPE_ARRAY.  The element type is
97  * passed in ELEMENT_INFO, and array length in LENGTH_EXPR.  If,
98  * respectively, OWN_INFO and OWN_LENGTH are true, the pointee and
99  * length are owned and destroyed together with INFO.  */
100 void type_init_array(struct arg_type_info *info,
101 		     struct arg_type_info *element_info, int own_info,
102 		     struct expr_node *length_expr, int own_length);
103 
104 /* Initialize INFO so it becomes ARGTYPE_POINTER.  The pointee type is
105  * passed in POINTEE_INFO.  If OWN_INFO, the pointee type is owned and
106  * destroyed together with INFO.  */
107 void type_init_pointer(struct arg_type_info *info,
108 		       struct arg_type_info *pointee_info, int own_info);
109 
110 /* Release any memory associated with INFO.  Doesn't free INFO
111  * itself.  */
112 void type_destroy(struct arg_type_info *info);
113 
114 /* Copy type INFO into the area pointed to by RETP.  Return 0 on
115  * success or a negative value on failure.  */
116 int type_clone(struct arg_type_info *retp, const struct arg_type_info *info);
117 
118 /* Compute a size of given type.  Return (size_t)-1 for error.  */
119 size_t type_sizeof(struct process *proc, struct arg_type_info *type);
120 
121 /* Compute an alignment necessary for elements of this type.  Return
122  * (size_t)-1 for error.  */
123 size_t type_alignof(struct process *proc, struct arg_type_info *type);
124 
125 /* Align value SZ to ALIGNMENT and return the result.  */
126 size_t align(size_t sz, size_t alignment);
127 
128 /* Return ELT-th element of compound type TYPE.  This is useful for
129  * arrays and structures.  */
130 struct arg_type_info *type_element(struct arg_type_info *type, size_t elt);
131 
132 /* Compute an offset of EMT-th element of type TYPE.  This works for
133  * arrays and structures.  Return (size_t)-1 for error.  */
134 size_t type_offsetof(struct process *proc,
135 		     struct arg_type_info *type, size_t elt);
136 
137 /* Whether TYPE is an integral type as defined by the C standard.  */
138 int type_is_integral(enum arg_type type);
139 
140 /* Whether TYPE, which shall be integral, is a signed type.  */
141 int type_is_signed(enum arg_type type);
142 
143 /* If INFO is floating point equivalent type, return the corresponding
144  * floating point type.  Otherwise return NULL.  Floating point
145  * equivalent types are either ARGTYPE_FLOAT, or ARGTYPE_DOUBLE, or
146  * ARGTYPE_STRUCT whose sole member is a floating point equivalent
147  * type.  */
148 struct arg_type_info *type_get_fp_equivalent(struct arg_type_info *info);
149 
150 /* If INFO is homogeneous floating-point aggregate, return the
151  * corresponding floating point type, and set *COUNTP to number of
152  * fields of the structure.  Otherwise return NULL.  INFO is a HFA if
153  * it's an aggregate whose each field is either a HFA, or a
154  * floating-point type.  */
155 struct arg_type_info *type_get_hfa_type(struct arg_type_info *info,
156 					size_t *countp);
157 
158 
159 #endif /* TYPE_H */
160