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hpack_table.h
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33 
34 #ifndef GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_TABLE_H
35 #define GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_TABLE_H
36 
39 #include <grpc/support/slice.h>
40 
41 /* HPACK header table */
42 
43 /* last index in the static table */
44 #define GRPC_CHTTP2_LAST_STATIC_ENTRY 61
45 
46 /* Initial table size as per the spec */
47 #define GRPC_CHTTP2_INITIAL_HPACK_TABLE_SIZE 4096
48 /* Maximum table size that we'll use */
49 #define GRPC_CHTTP2_MAX_HPACK_TABLE_SIZE GRPC_CHTTP2_INITIAL_HPACK_TABLE_SIZE
50 /* Per entry overhead bytes as per the spec */
51 #define GRPC_CHTTP2_HPACK_ENTRY_OVERHEAD 32
52 /* Maximum number of entries we could possibly fit in the table, given defined
53  overheads */
54 #define GRPC_CHTTP2_MAX_TABLE_COUNT \
55  ((GRPC_CHTTP2_MAX_HPACK_TABLE_SIZE + GRPC_CHTTP2_HPACK_ENTRY_OVERHEAD - 1) / \
56  GRPC_CHTTP2_HPACK_ENTRY_OVERHEAD)
57 
58 /* hpack decoder table */
59 typedef struct {
61  /* the first used entry in ents */
63  /* the last used entry in ents */
65  /* how many entries are in the table */
67  /* the amount of memory used by the table, according to the hpack algorithm */
69  /* the max memory allowed to be used by the table, according to the hpack
70  algorithm */
72  /* a circular buffer of headers - this is stored in the opposite order to
73  what hpack specifies, in order to simplify table management a little...
74  meaning lookups need to SUBTRACT from the end position */
78 
79 /* initialize a hpack table */
82 
83 /* lookup a table entry based on its hpack index */
85  gpr_uint32 index);
86 /* add a table entry to the index */
88 /* Find a key/value pair in the table... returns the index in the table of the
89  most similar entry, or 0 if the value was not found */
90 typedef struct {
95  const grpc_chttp2_hptbl *tbl, grpc_mdelem *md);
96 
97 #endif /* GRPC_INTERNAL_CORE_TRANSPORT_CHTTP2_HPACK_TABLE_H */
void grpc_chttp2_hptbl_destroy(grpc_chttp2_hptbl *tbl)
Definition: hpack_table.c:122
uint8_t gpr_uint8
Definition: port_platform.h:310
gpr_uint16 index
Definition: hpack_table.h:91
gpr_uint16 max_bytes
Definition: hpack_table.h:71
#define GRPC_CHTTP2_LAST_STATIC_ENTRY
Definition: hpack_table.h:44
Definition: hpack_table.h:59
uint32_t gpr_uint32
Definition: port_platform.h:312
grpc_mdelem * grpc_chttp2_hptbl_lookup(const grpc_chttp2_hptbl *tbl, gpr_uint32 index)
Definition: hpack_table.c:133
gpr_uint16 num_ents
Definition: hpack_table.h:66
grpc_mdctx * mdctx
Definition: hpack_table.h:60
gpr_uint16 last_ent
Definition: hpack_table.h:64
Definition: metadata.c:98
Definition: metadata.h:78
void grpc_chttp2_hptbl_add(grpc_chttp2_hptbl *tbl, grpc_mdelem *md)
Definition: hpack_table.c:161
uint16_t gpr_uint16
Definition: port_platform.h:311
gpr_uint16 first_ent
Definition: hpack_table.h:62
grpc_chttp2_hptbl_find_result grpc_chttp2_hptbl_find(const grpc_chttp2_hptbl *tbl, grpc_mdelem *md)
Definition: hpack_table.c:198
gpr_uint8 has_value
Definition: hpack_table.h:92
Definition: hpack_table.h:90
#define GRPC_CHTTP2_MAX_TABLE_COUNT
Definition: hpack_table.h:54
gpr_uint16 mem_used
Definition: hpack_table.h:68
void grpc_chttp2_hptbl_init(grpc_chttp2_hptbl *tbl, grpc_mdctx *mdctx)
Definition: hpack_table.c:110