xref: /netbsd-src/external/gpl3/gdb/dist/include/sframe-api.h (revision 901e7e84758515fbf39dfc064cb0b45ab146d8b0)
1 /* Public API to SFrame.
2 
3    Copyright (C) 2022 Free Software Foundation, Inc.
4 
5    This file is part of libsframe.
6 
7    This program is free software; you can redistribute it and/or modify
8    it under the terms of the GNU General Public License as published by
9    the Free Software Foundation; either version 3 of the License, or
10    (at your option) any later version.
11 
12    This program is distributed in the hope that it will be useful,
13    but WITHOUT ANY WARRANTY; without even the implied warranty of
14    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
15    GNU General Public License for more details.
16 
17    You should have received a copy of the GNU General Public License
18    along with this program.  If not, see <http://www.gnu.org/licenses/>.  */
19 
20 #ifndef	_SFRAME_API_H
21 #define	_SFRAME_API_H
22 
23 #include <sframe.h>
24 #include <stdbool.h>
25 
26 #ifdef	__cplusplus
27 extern "C"
28 {
29 #endif
30 
31 typedef struct sframe_decoder_ctx sframe_decoder_ctx;
32 typedef struct sframe_encoder_ctx sframe_encoder_ctx;
33 
34 #define MAX_OFFSET_BYTES (SFRAME_FRE_OFFSET_4B * 2 * 3)
35 
36 /* User interfacing SFrame Row Entry.
37    An abstraction provided by libsframe so the consumer is decoupled from
38    the binary format representation of the same.
39 
40    The members are best ordered such that they are aligned at their natural
41    boundaries.  This helps avoid usage of undesirable misaligned memory
42    accesses.  See PR libsframe/29856.  */
43 
44 typedef struct sframe_frame_row_entry
45 {
46   uint32_t fre_start_addr;
47   unsigned char fre_offsets[MAX_OFFSET_BYTES];
48   unsigned char fre_info;
49 } sframe_frame_row_entry;
50 
51 #define SFRAME_ERR ((int) -1)
52 
53 /* This macro holds information about all the available SFrame
54    errors.  It is used to form both an enum holding all the error
55    constants, and also the error strings themselves.  To use, define
56    _SFRAME_FIRST and _SFRAME_ITEM to expand as you like, then
57    mention the macro name.  See the enum after this for an example.  */
58 #define _SFRAME_ERRORS \
59   _SFRAME_FIRST (SFRAME_ERR_VERSION_INVAL, "SFrame version not supported.") \
60   _SFRAME_ITEM (SFRAME_ERR_NOMEM, "Out of Memory.") \
61   _SFRAME_ITEM (SFRAME_ERR_INVAL, "Corrupt SFrame.") \
62   _SFRAME_ITEM (SFRAME_ERR_BUF_INVAL, "Buffer does not contain SFrame data.") \
63   _SFRAME_ITEM (SFRAME_ERR_DCTX_INVAL, "Corrupt SFrame decoder.") \
64   _SFRAME_ITEM (SFRAME_ERR_ECTX_INVAL, "Corrupt SFrame encoder.") \
65   _SFRAME_ITEM (SFRAME_ERR_FDE_INVAL, "Corrput FDE.") \
66   _SFRAME_ITEM (SFRAME_ERR_FRE_INVAL, "Corrupt FRE.") \
67   _SFRAME_ITEM (SFRAME_ERR_FDE_NOTFOUND,"FDE not found.") \
68   _SFRAME_ITEM (SFRAME_ERR_FDE_NOTSORTED, "FDEs not sorted.") \
69   _SFRAME_ITEM (SFRAME_ERR_FRE_NOTFOUND,"FRE not found.") \
70   _SFRAME_ITEM (SFRAME_ERR_FREOFFSET_NOPRESENT,"FRE offset not present.")
71 
72 #define	SFRAME_ERR_BASE	2000	/* Base value for libsframe errnos.  */
73 
74 enum
75   {
76 #define _SFRAME_FIRST(NAME, STR) NAME = SFRAME_ERR_BASE
77 #define _SFRAME_ITEM(NAME, STR) , NAME
78 _SFRAME_ERRORS
79 #undef _SFRAME_ITEM
80 #undef _SFRAME_FIRST
81   };
82 
83 /* Count of SFrame errors.  */
84 #define SFRAME_ERR_NERR (SFRAME_ERR_FREOFFSET_NOPRESENT - SFRAME_ERR_BASE + 1)
85 
86 /* Get the error message string.  */
87 
88 extern const char *
89 sframe_errmsg (int error);
90 
91 /* Create an FDE function info bye given an FRE_TYPE and an FDE_TYPE.  */
92 
93 extern unsigned char
94 sframe_fde_create_func_info (unsigned int fre_type, unsigned int fde_type);
95 
96 /* Gather the FRE type given the function size.  */
97 
98 extern unsigned int
99 sframe_calc_fre_type (unsigned int func_size);
100 
101 /* The SFrame Decoder.  */
102 
103 /* Decode the specified SFrame buffer CF_BUF of size CF_SIZE and return the
104    new SFrame decoder context.  Sets ERRP for the caller if any error.  */
105 extern sframe_decoder_ctx *
106 sframe_decode (const char *cf_buf, size_t cf_size, int *errp);
107 
108 /* Free the decoder context.  */
109 extern void
110 sframe_decoder_free (sframe_decoder_ctx **dctx);
111 
112 /* Get the size of the SFrame header from the decoder context DCTX.  */
113 extern unsigned int
114 sframe_decoder_get_hdr_size (sframe_decoder_ctx *dctx);
115 
116 /* Get the SFrame's abi/arch info.  */
117 extern unsigned char
118 sframe_decoder_get_abi_arch (sframe_decoder_ctx *dctx);
119 
120 /* Return the number of function descriptor entries in the SFrame decoder
121    DCTX.  */
122 unsigned int
123 sframe_decoder_get_num_fidx (sframe_decoder_ctx *dctx);
124 
125 /* Get the fixed FP offset from the decoder context DCTX.  */
126 extern int8_t
127 sframe_decoder_get_fixed_fp_offset (sframe_decoder_ctx *dctx);
128 
129 /* Get the fixed RA offset from the decoder context DCTX.  */
130 extern int8_t
131 sframe_decoder_get_fixed_ra_offset (sframe_decoder_ctx *dctx);
132 
133 /* Find the function descriptor entry which contains the specified address.  */
134 extern sframe_func_desc_entry *
135 sframe_get_funcdesc_with_addr (sframe_decoder_ctx *dctx,
136 			       int32_t addr, int *errp);
137 
138 /* Find the SFrame Frame Row Entry which contains the PC.  Returns
139    SFRAME_ERR if failure.  */
140 
141 extern int
142 sframe_find_fre (sframe_decoder_ctx *ctx, int32_t pc,
143 		 sframe_frame_row_entry *frep);
144 
145 /* Get the FRE_IDX'th FRE of the function at FUNC_IDX'th function
146    index entry in the SFrame decoder CTX.  Returns error code as
147    applicable.  */
148 extern int
149 sframe_decoder_get_fre (sframe_decoder_ctx *ctx,
150 			unsigned int func_idx,
151 			unsigned int fre_idx,
152 			sframe_frame_row_entry *fre);
153 
154 /* Get the data (NUM_FRES, FUNC_START_ADDRESS) from the function
155    descriptor entry at index I'th in the decoder CTX.  If failed,
156    return error code.  */
157 extern int
158 sframe_decoder_get_funcdesc (sframe_decoder_ctx *ctx,
159 			     unsigned int i,
160 			     uint32_t *num_fres,
161 			     uint32_t *func_size,
162 			     int32_t *func_start_address,
163 			     unsigned char *func_info);
164 
165 /* SFrame textual dump.  */
166 extern void
167 dump_sframe (sframe_decoder_ctx *decoder, uint64_t addr);
168 
169 /* Get the base reg id from the FRE info.  Sets errp if fails.  */
170 extern unsigned int
171 sframe_fre_get_base_reg_id (sframe_frame_row_entry *fre, int *errp);
172 
173 /* Get the CFA offset from the FRE.  If the offset is invalid, sets errp.  */
174 extern int32_t
175 sframe_fre_get_cfa_offset (sframe_decoder_ctx *dtcx,
176 			   sframe_frame_row_entry *fre, int *errp);
177 
178 /* Get the FP offset from the FRE.  If the offset is invalid, sets errp.  */
179 extern int32_t
180 sframe_fre_get_fp_offset (sframe_decoder_ctx *dctx,
181 			  sframe_frame_row_entry *fre, int *errp);
182 
183 /* Get the RA offset from the FRE.  If the offset is invalid, sets errp.  */
184 extern int32_t
185 sframe_fre_get_ra_offset (sframe_decoder_ctx *dctx,
186 			  sframe_frame_row_entry *fre, int *errp);
187 
188 /* Get whether the RA is mangled.  */
189 
190 extern bool
191 sframe_fre_get_ra_mangled_p (sframe_decoder_ctx *dctx,
192 			     sframe_frame_row_entry *fre, int *errp);
193 
194 /* The SFrame Encoder.  */
195 
196 /* Create an encoder context with the given SFrame format version VER, FLAGS
197    and ABI information.  Sets errp if failure.  */
198 extern sframe_encoder_ctx *
199 sframe_encode (unsigned char ver, unsigned char flags, int abi,
200 	       int8_t fixed_fp_offset, int8_t fixed_ra_offset, int *errp);
201 
202 /* Free the encoder context.  */
203 extern void
204 sframe_encoder_free (sframe_encoder_ctx **encoder);
205 
206 /* Get the size of the SFrame header from the encoder ctx ENCODER.  */
207 extern unsigned int
208 sframe_encoder_get_hdr_size (sframe_encoder_ctx *encoder);
209 
210 /* Get the abi/arch info from the SFrame encoder context CTX.  */
211 extern unsigned char
212 sframe_encoder_get_abi_arch (sframe_encoder_ctx *encoder);
213 
214 /* Return the number of function descriptor entries in the SFrame encoder
215    ENCODER.  */
216 extern unsigned int
217 sframe_encoder_get_num_fidx (sframe_encoder_ctx *encoder);
218 
219 /* Add an FRE to function at FUNC_IDX'th function descriptor index entry in
220    the encoder context.  */
221 extern int
222 sframe_encoder_add_fre (sframe_encoder_ctx *encoder,
223 			unsigned int func_idx,
224 			sframe_frame_row_entry *frep);
225 
226 /* Add a new function descriptor entry with START_ADDR, FUNC_SIZE and NUM_FRES
227    to the encoder.  */
228 extern int
229 sframe_encoder_add_funcdesc (sframe_encoder_ctx *encoder,
230 			     int32_t start_addr,
231 			     uint32_t func_size,
232 			     unsigned char func_info,
233 			     uint32_t num_fres);
234 
235 /* Serialize the contents of the encoder and return the buffer.  ENCODED_SIZE
236    is updated to the size of the buffer.  Sets ERRP if failure.  */
237 extern char  *
238 sframe_encoder_write (sframe_encoder_ctx *encoder,
239 		      size_t *encoded_size, int *errp);
240 
241 #ifdef	__cplusplus
242 }
243 #endif
244 
245 #endif				/* _SFRAME_API_H */
246