src/include/libpq/pqformat.h

   1 /*-------------------------------------------------------------------------
   2  *
   3  * pqformat.h
   4  *              Definitions for formatting and parsing frontend/backend messages
   5  *
   6  * Portions Copyright (c) 1996-2023, PostgreSQL Global Development Group
   7  * Portions Copyright (c) 1994, Regents of the University of California
   8  *
   9  * src/include/libpq/pqformat.h
  10  *
  11  *-------------------------------------------------------------------------
  12  */
  13 #ifndef PQFORMAT_H
  14 #define PQFORMAT_H
  15
  16 #include "lib/stringinfo.h"
  17 #include "mb/pg_wchar.h"
  18 #include "port/pg_bswap.h"
  19
  20 extern void pq_beginmessage(StringInfo buf, char msgtype);
  21 extern void pq_beginmessage_reuse(StringInfo buf, char msgtype);
  22 extern void pq_endmessage(StringInfo buf);
  23 extern void pq_endmessage_reuse(StringInfo buf);
  24
  25 extern void pq_sendbytes(StringInfo buf, const void *data, int datalen);
  26 extern void pq_sendcountedtext(StringInfo buf, const char *str, int slen,
  27                                                            bool countincludesself);
  28 extern void pq_sendtext(StringInfo buf, const char *str, int slen);
  29 extern void pq_sendstring(StringInfo buf, const char *str);
  30 extern void pq_send_ascii_string(StringInfo buf, const char *str);
  31 extern void pq_sendfloat4(StringInfo buf, float4 f);
  32 extern void pq_sendfloat8(StringInfo buf, float8 f);
  33
  34 /*
  35  * Append a [u]int8 to a StringInfo buffer, which already has enough space
  36  * preallocated.
  37  *
  38  * The use of pg_restrict allows the compiler to optimize the code based on
  39  * the assumption that buf, buf->len, buf->data and *buf->data don't
  40  * overlap. Without the annotation buf->len etc cannot be kept in a register
  41  * over subsequent pq_writeintN calls.
  42  *
  43  * The use of StringInfoData * rather than StringInfo is due to MSVC being
  44  * overly picky and demanding a * before a restrict.
  45  */
  46 static inline void
  47 pq_writeint8(StringInfoData *pg_restrict buf, uint8 i)
  48 {
  49         uint8           ni = i;
  50
  51         Assert(buf->len + (int) sizeof(uint8) <= buf->maxlen);
  52         memcpy((char *pg_restrict) (buf->data + buf->len), &ni, sizeof(uint8));
  53         buf->len += sizeof(uint8);
  54 }
  55
  56 /*
  57  * Append a [u]int16 to a StringInfo buffer, which already has enough space
  58  * preallocated.
  59  */
  60 static inline void
  61 pq_writeint16(StringInfoData *pg_restrict buf, uint16 i)
  62 {
  63         uint16          ni = pg_hton16(i);
  64
  65         Assert(buf->len + (int) sizeof(uint16) <= buf->maxlen);
  66         memcpy((char *pg_restrict) (buf->data + buf->len), &ni, sizeof(uint16));
  67         buf->len += sizeof(uint16);
  68 }
  69
  70 /*
  71  * Append a [u]int32 to a StringInfo buffer, which already has enough space
  72  * preallocated.
  73  */
  74 static inline void
  75 pq_writeint32(StringInfoData *pg_restrict buf, uint32 i)
  76 {
  77         uint32          ni = pg_hton32(i);
  78
  79         Assert(buf->len + (int) sizeof(uint32) <= buf->maxlen);
  80         memcpy((char *pg_restrict) (buf->data + buf->len), &ni, sizeof(uint32));
  81         buf->len += sizeof(uint32);
  82 }
  83
  84 /*
  85  * Append a [u]int64 to a StringInfo buffer, which already has enough space
  86  * preallocated.
  87  */
  88 static inline void
  89 pq_writeint64(StringInfoData *pg_restrict buf, uint64 i)
  90 {
  91         uint64          ni = pg_hton64(i);
  92
  93         Assert(buf->len + (int) sizeof(uint64) <= buf->maxlen);
  94         memcpy((char *pg_restrict) (buf->data + buf->len), &ni, sizeof(uint64));
  95         buf->len += sizeof(uint64);
  96 }
  97
  98 /*
  99  * Append a null-terminated text string (with conversion) to a buffer with
 100  * preallocated space.
 101  *
 102  * NB: The pre-allocated space needs to be sufficient for the string after
 103  * converting to client encoding.
 104  *
 105  * NB: passed text string must be null-terminated, and so is the data
 106  * sent to the frontend.
 107  */
 108 static inline void
 109 pq_writestring(StringInfoData *pg_restrict buf, const char *pg_restrict str)
 110 {
 111         int                     slen = strlen(str);
 112         char       *p;
 113
 114         p = pg_server_to_client(str, slen);
 115         if (p != str)                           /* actual conversion has been done? */
 116                 slen = strlen(p);
 117
 118         Assert(buf->len + slen + 1 <= buf->maxlen);
 119
 120         memcpy(((char *pg_restrict) buf->data + buf->len), p, slen + 1);
 121         buf->len += slen + 1;
 122
 123         if (p != str)
 124                 pfree(p);
 125 }
 126
 127 /* append a binary [u]int8 to a StringInfo buffer */
 128 static inline void
 129 pq_sendint8(StringInfo buf, uint8 i)
 130 {
 131         enlargeStringInfo(buf, sizeof(uint8));
 132         pq_writeint8(buf, i);
 133 }
 134
 135 /* append a binary [u]int16 to a StringInfo buffer */
 136 static inline void
 137 pq_sendint16(StringInfo buf, uint16 i)
 138 {
 139         enlargeStringInfo(buf, sizeof(uint16));
 140         pq_writeint16(buf, i);
 141 }
 142
 143 /* append a binary [u]int32 to a StringInfo buffer */
 144 static inline void
 145 pq_sendint32(StringInfo buf, uint32 i)
 146 {
 147         enlargeStringInfo(buf, sizeof(uint32));
 148         pq_writeint32(buf, i);
 149 }
 150
 151 /* append a binary [u]int64 to a StringInfo buffer */
 152 static inline void
 153 pq_sendint64(StringInfo buf, uint64 i)
 154 {
 155         enlargeStringInfo(buf, sizeof(uint64));
 156         pq_writeint64(buf, i);
 157 }
 158
 159 /* append a binary byte to a StringInfo buffer */
 160 static inline void
 161 pq_sendbyte(StringInfo buf, uint8 byt)
 162 {
 163         pq_sendint8(buf, byt);
 164 }
 165
 166 /*
 167  * Append a binary integer to a StringInfo buffer
 168  *
 169  * This function is deprecated; prefer use of the functions above.
 170  */
 171 static inline void
 172 pq_sendint(StringInfo buf, uint32 i, int b)
 173 {
 174         switch (b)
 175         {
 176                 case 1:
 177                         pq_sendint8(buf, (uint8) i);
 178                         break;
 179                 case 2:
 180                         pq_sendint16(buf, (uint16) i);
 181                         break;
 182                 case 4:
 183                         pq_sendint32(buf, (uint32) i);
 184                         break;
 185                 default:
 186                         elog(ERROR, "unsupported integer size %d", b);
 187                         break;
 188         }
 189 }
 190
 191
 192 extern void pq_begintypsend(StringInfo buf);
 193 extern bytea *pq_endtypsend(StringInfo buf);
 194
 195 extern void pq_puttextmessage(char msgtype, const char *str);
 196 extern void pq_putemptymessage(char msgtype);
 197
 198 extern int      pq_getmsgbyte(StringInfo msg);
 199 extern unsigned int pq_getmsgint(StringInfo msg, int b);
 200 extern int64 pq_getmsgint64(StringInfo msg);
 201 extern float4 pq_getmsgfloat4(StringInfo msg);
 202 extern float8 pq_getmsgfloat8(StringInfo msg);
 203 extern const char *pq_getmsgbytes(StringInfo msg, int datalen);
 204 extern void pq_copymsgbytes(StringInfo msg, char *buf, int datalen);
 205 extern char *pq_getmsgtext(StringInfo msg, int rawbytes, int *nbytes);
 206 extern const char *pq_getmsgstring(StringInfo msg);
 207 extern const char *pq_getmsgrawstring(StringInfo msg);
 208 extern void pq_getmsgend(StringInfo msg);
 209
 210 #endif                                                  /* PQFORMAT_H */