]> git.stg.codes - stg.git/blob - libs/smux/per_encoder.c
Add instrumentation.
[stg.git] / libs / smux / per_encoder.c
1 #include <asn_application.h>
2 #include <asn_internal.h>
3 #include <per_encoder.h>
4
5 static asn_enc_rval_t uper_encode_internal(asn_TYPE_descriptor_t *td, asn_per_constraints_t *, void *sptr, asn_app_consume_bytes_f *cb, void *app_key);
6
7 asn_enc_rval_t
8 uper_encode(asn_TYPE_descriptor_t *td, void *sptr, asn_app_consume_bytes_f *cb, void *app_key) {
9         return uper_encode_internal(td, 0, sptr, cb, app_key);
10 }
11
12 /*
13  * Argument type and callback necessary for uper_encode_to_buffer().
14  */
15 typedef struct enc_to_buf_arg {
16         void *buffer;
17         size_t left;
18 } enc_to_buf_arg;
19 static int encode_to_buffer_cb(const void *buffer, size_t size, void *key) {
20         enc_to_buf_arg *arg = (enc_to_buf_arg *)key;
21
22         if(arg->left < size)
23                 return -1;      /* Data exceeds the available buffer size */
24
25         memcpy(arg->buffer, buffer, size);
26         arg->buffer = ((char *)arg->buffer) + size;
27         arg->left -= size;
28
29         return 0;
30 }
31
32 asn_enc_rval_t
33 uper_encode_to_buffer(asn_TYPE_descriptor_t *td, void *sptr, void *buffer, size_t buffer_size) {
34         enc_to_buf_arg key;
35
36         key.buffer = buffer;
37         key.left = buffer_size;
38
39         if(td) ASN_DEBUG("Encoding \"%s\" using UNALIGNED PER", td->name);
40
41         return uper_encode_internal(td, 0, sptr, encode_to_buffer_cb, &key);
42 }
43
44 typedef struct enc_dyn_arg {
45         void *buffer;
46         size_t length;
47         size_t allocated;
48 } enc_dyn_arg;
49 static int
50 encode_dyn_cb(const void *buffer, size_t size, void *key) {
51         enc_dyn_arg *arg = key;
52         if(arg->length + size >= arg->allocated) {
53                 void *p;
54                 arg->allocated = arg->allocated ? (arg->allocated << 2) : size;
55                 p = REALLOC(arg->buffer, arg->allocated);
56                 if(!p) {
57                         FREEMEM(arg->buffer);
58                         memset(arg, 0, sizeof(*arg));
59                         return -1;
60                 }
61                 arg->buffer = p;
62         }
63         memcpy(((char *)arg->buffer) + arg->length, buffer, size);
64         arg->length += size;
65         return 0;
66 }
67 ssize_t
68 uper_encode_to_new_buffer(asn_TYPE_descriptor_t *td, asn_per_constraints_t *constraints, void *sptr, void **buffer_r) {
69         asn_enc_rval_t er;
70         enc_dyn_arg key;
71
72         memset(&key, 0, sizeof(key));
73
74         er = uper_encode_internal(td, constraints, sptr, encode_dyn_cb, &key);
75         switch(er.encoded) {
76         case -1:
77                 FREEMEM(key.buffer);
78                 return -1;
79         case 0:
80                 FREEMEM(key.buffer);
81                 key.buffer = MALLOC(1);
82                 if(key.buffer) {
83                         *(char *)key.buffer = '\0';
84                         *buffer_r = key.buffer;
85                         return 1;
86                 } else {
87                         return -1;
88                 }
89         default:
90                 *buffer_r = key.buffer;
91                 ASN_DEBUG("Complete encoded in %ld bits", (long)er.encoded);
92                 return ((er.encoded + 7) >> 3);
93         }
94 }
95
96 /*
97  * Internally useful functions.
98  */
99
100 /* Flush partially filled buffer */
101 static int
102 _uper_encode_flush_outp(asn_per_outp_t *po) {
103         uint8_t *buf;
104
105         if(po->nboff == 0 && po->buffer == po->tmpspace)
106                 return 0;
107
108         buf = po->buffer + (po->nboff >> 3);
109         /* Make sure we account for the last, partially filled */
110         if(po->nboff & 0x07) {
111                 buf[0] &= 0xff << (8 - (po->nboff & 0x07));
112                 buf++;
113         }
114
115         return po->outper(po->tmpspace, buf - po->tmpspace, po->op_key);
116 }
117
118 static asn_enc_rval_t
119 uper_encode_internal(asn_TYPE_descriptor_t *td, asn_per_constraints_t *constraints, void *sptr, asn_app_consume_bytes_f *cb, void *app_key) {
120         asn_per_outp_t po;
121         asn_enc_rval_t er;
122
123         /*
124          * Invoke type-specific encoder.
125          */
126         if(!td || !td->uper_encoder)
127                 ASN__ENCODE_FAILED;     /* PER is not compiled in */
128
129         po.buffer = po.tmpspace;
130         po.nboff = 0;
131         po.nbits = 8 * sizeof(po.tmpspace);
132         po.outper = cb;
133         po.op_key = app_key;
134         po.flushed_bytes = 0;
135
136         er = td->uper_encoder(td, constraints, sptr, &po);
137         if(er.encoded != -1) {
138                 size_t bits_to_flush;
139
140                 bits_to_flush = ((po.buffer - po.tmpspace) << 3) + po.nboff;
141
142                 /* Set number of bits encoded to a firm value */
143                 er.encoded = (po.flushed_bytes << 3) + bits_to_flush;
144
145                 if(_uper_encode_flush_outp(&po))
146                         ASN__ENCODE_FAILED;
147         }
148
149         return er;
150 }
151