vg_msg.h

   1 #pragma once
   2 /*
   3  * Example data:
   4  *   kvstr "someinfo"
   5  *   kvint 200
   6  *   frame "person"{
   7  *      name "jeff"
   8  *      country "england"
   9  *   }
  10  *   frame "building"{
  11  *      capacity 1000
  12  *   }
  13  *   frame "person"{
  14  *      country "wales"
  15  *      name "micheal"
  16  *   }
  17  *
  18  * Creating the data in code:
  19  * -----------------------------------------------------------------------------
  20  *   u8 data_buf[512];
  21  *   vg_msg data;
  22  *   vg_msg_init( &data, data_buf, 512 );
  23  *
  24  *   vg_msg_wkvstr( &data, "kvstr", "someinfo" );
  25  *   vg_msg_wkvu32( &data, "kvint", 200 );
  26  *
  27  *   vg_msg_frame( &data, "person" );
  28  *      vg_msg_wkvstr( &data, "name", "jeff" );
  29  *      vg_msg_wkvstr( &data, "country", "england" );
  30  *   vg_msg_end_frame( &data );
  31  *
  32  *   vg_msg_frame( &data, "building" );
  33  *      vg_msg_wkvu32( &data, "capacity", 1000 );
  34  *   vg_msg_end_frame( &data );
  35  *
  36  *   vg_msg_frame( &data, "person" );
  37  *      vg_msg_wkvstr( &data, "country", "wales" );
  38  *      vg_msg_wkvstr( &data, "name", "micheal" );
  39  *   vg_msg_end_frame( &data );
  40  *
  41  * Saving the data out
  42  * -----------------------------------------------------------------------------
  43  *
  44  *   if( data.error == k_vg_msg_error_OK ){
  45  *      // write data_buf, for length data.cur
  46  *   }
  47  *
  48  * Load the data
  49  * -----------------------------------------------------------------------------
  50  *
  51  *   u8 data_buf[512];
  52  *   u32 data_len;
  53  *
  54  *   // read data_buf and data_len
  55  *
  56  *   vg_msg data;
  57  *   vg_msg_init( &data, data_buf, data_len );
  58  *
  59  *
  60  * Reading data
  61  * -----------------------------------------------------------------------------
  62  *
  63  * if( vg_msg_seekframe( &msg, "rows" ) ){
  64  *    while( vg_msg_seekframe( &msg, NULL ) ){
  65  *       vg_warn( "%s\n", vg_msg_readkvstr( &msg, "yedo" ) );
  66  *       vg_msg_skip_frame( &msg );
  67  *    }
  68  * }
  69  *
  70  * Reading back the stream linearly
  71  * -----------------------------------------------------------------------------
  72  *
  73  *   vg_msg_cmd cmd;
  74  *   while( vg_msg_next( &data, &cmd ) ){
  75  *           if( cmd.code == k_vg_msg_frame ) printf( "{" );
  76  *      else if( cmd.code == k_vg_msg_endframe ) printf( "}" );
  77  *      esle if( cmd.code == k_vg_msg_kvstring )
  78  *         printf( "string: %s\n", cmd.value._buf );
  79  *   }
  80  */
  81
  82 enum vg_msg_code{
  83    /* low types */
  84    k_vg_msg_end      = 0,
  85    k_vg_msg_frame    = 1,
  86    k_vg_msg_endframe = 2,
  87    k_vg_msg_kv       = 10,
  88    k_vg_msg_kvstring = 11,
  89    k_vg_msg_kvbin    = 12,
  90
  91    /* variable sized types */
  92    k_vg_msg_float    = 0x40,
  93    k_vg_msg_unsigned = 0x80,
  94    k_vg_msg_signed   = 0xC0,
  95
  96    /* masks */
  97    k_vg_msg_array_count_bits = 0x3C,
  98    k_vg_msg_type_size_bits   = 0x03,
  99    k_vg_msg_type_base_bits   = 0xC0,
 100    k_vg_msg_type_bits        = k_vg_msg_type_base_bits|k_vg_msg_type_size_bits,
 101
 102    /* sizes */
 103    k_vg_msg_8b  = 0x00,
 104    k_vg_msg_16b = 0x01,
 105    k_vg_msg_32b = 0x02,
 106    k_vg_msg_64b = 0x03,
 107
 108    /* common types */
 109    k_vg_msg_u8  = k_vg_msg_unsigned|k_vg_msg_8b,
 110    k_vg_msg_u16 = k_vg_msg_unsigned|k_vg_msg_16b,
 111    k_vg_msg_u32 = k_vg_msg_unsigned|k_vg_msg_32b,
 112    k_vg_msg_u64 = k_vg_msg_unsigned|k_vg_msg_64b,
 113    k_vg_msg_i8  = k_vg_msg_signed  |k_vg_msg_8b,
 114    k_vg_msg_i16 = k_vg_msg_signed  |k_vg_msg_16b,
 115    k_vg_msg_i32 = k_vg_msg_signed  |k_vg_msg_32b,
 116    k_vg_msg_i64 = k_vg_msg_signed  |k_vg_msg_64b,
 117    k_vg_msg_f32 = k_vg_msg_float   |k_vg_msg_32b,
 118    k_vg_msg_f64 = k_vg_msg_float   |k_vg_msg_64b,
 119
 120    k_vg_msg_v2f = k_vg_msg_float   |k_vg_msg_32b | (1<<2),
 121    k_vg_msg_v3f = k_vg_msg_float   |k_vg_msg_32b | (2<<2),
 122    k_vg_msg_v4f = k_vg_msg_float   |k_vg_msg_32b | (3<<2)
 123 };
 124
 125 typedef struct vg_msg vg_msg;
 126 typedef struct vg_msg_cmd vg_msg_cmd;
 127 typedef struct vg_msg_cursor vg_msg_cursor;
 128 struct vg_msg
 129 {
 130    u32 max;
 131    u8 *buf;
 132
 133    /* reading */
 134    struct vg_msg_cursor
 135    {
 136       u32 co, depth;
 137    }
 138    cur;
 139
 140    enum vg_msg_error
 141    {
 142       k_vg_msg_error_OK,
 143       k_vg_msg_error_unbalanced,
 144       k_vg_msg_error_overflow,
 145       k_vg_msg_error_unhandled_cmd
 146    }
 147    error;
 148 };
 149
 150 struct vg_msg_cmd
 151 {
 152    u8 code;
 153
 154    const char *key;
 155    u32 key_djb2;
 156
 157    const void *value;
 158    u32 value_djb2;
 159
 160    u32 len; /* set if binary type */
 161 };
 162
 163 void vg_msg_wbuf( vg_msg *msg, u8 *buf, u32 len );
 164 void vg_msg_rbuf( vg_msg *msg, u8 *buf, u32 len );
 165 void vg_msg_wstr( vg_msg *msg, const char *str );
 166 const char *vg_msg_rstr( vg_msg *msg, u32 *djb2 );
 167 void vg_msg_frame( vg_msg *msg, const char *name );
 168 void vg_msg_end_frame( vg_msg *msg );
 169 void vg_msg_wkvstr( vg_msg *msg, const char *key, const char *value );
 170 void vg_msg_wkvbin( vg_msg *msg, const char *key, u8 *bin, u32 len );
 171 void vg_msg_wkvnum( vg_msg *msg, const char *key,
 172                     u8 type, u8 count, void *data );
 173 u32 vg_msg_cmd_array_count( u8 code );
 174 u32 vg_msg_cmd_type_size( u8 code );
 175 u32 vg_msg_cmd_bytecount( u8 code );
 176 u8 vg_msg_count_bits( u32 count );
 177
 178 void vg_msg_init( vg_msg *msg, u8 *buffer, u32 len );
 179 int vg_msg_next( vg_msg *msg, vg_msg_cmd *cmd );
 180 int vg_msg_skip_frame( vg_msg *msg );
 181 int vg_msg_seekframe( vg_msg *msg, const char *name );
 182 u64 vg_msg_cast_to_u64( const void *src, u8 src_base, u8 src_size );
 183 i64 vg_msg_cast_to_i64( const void *src, u8 src_base, u8 src_size );
 184 f64 vg_msg_cast_to_f64( const void *src, u8 src_base, u8 src_size );
 185 void vg_msg_cast( const void *src, u8 src_code, void *dst, u8 dst_code );
 186
 187 int vg_msg_getkvcmd( vg_msg *msg, const char *key, vg_msg_cmd *cmd );
 188
 189 /*
 190  * Read a integral KV out to dst, and perform conversion if needed
 191  */
 192 int vg_msg_getkvintg( vg_msg *msg, const char *key, u8 type, void *dst,
 193                       void *default_value );
 194
 195 /* helper for reading string kvs. returns NULL if not found */
 196 const char *vg_msg_getkvstr( vg_msg *msg, const char *key );
 197 int vg_msg_getkvvecf( vg_msg *msg, const char *key, u8 type,
 198                       void *v, void *default_value );
 199 void vg_msg_print( vg_msg *msg, u32 len );