FixedHash - Revision history

imported>Leoetlino: /* Entry */ data size

2020-04-18T08:52:33Z

Entry: data size

← Older revision		Revision as of 08:52, 18 April 2020
Line 64:		Line 64:
	\|-		\|-
	\| 0xC \|\| u32 \|\| '''Data offset''' (relative to the Data section)		\| 0xC \|\| u32 \|\| '''Data offset''' (relative to the Data section)

			For non-node data, the data size is stored at offset+0 as a u64 and the actual data is at offset+8.
	\|-		\|-
	\|}		\|}
	[[Category:File formats]]		[[Category:File formats]]

imported>Leoetlino: bold

2020-04-17T13:57:43Z

bold

← Older revision		Revision as of 13:57, 17 April 2020
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	\| 0x8 \|\| u32[N + 1] \|\| '''Offsets to the first entry in each bucket''' (relative to the Entries section)<br>0xFFFFFFFF for empty buckets.		\| 0x8 \|\| u32[N + 1] \|\| '''Offsets to the first entry in each bucket''' (relative to the Entries section)<br>0xFFFFFFFF for empty buckets.
	\|-		\|-
	\| X = (0x8 + 4*(N+1) + 3) & -8 \|\| u64 \|\| Entries section size		\| X = (0x8 + 4*(N+1) + 3) & -8 \|\| u64 \|\| '''Entries section size'''
	\|-		\|-
	\| X + 8 \|\| Entry[...] \|\| '''Entries'''		\| X + 8 \|\| Entry[...] \|\| '''Entries'''
	\|-		\|-
	\| Y = align(X + entries section size, 8) \|\| u64 \|\| Entry offsets section size		\| Y = align(X + entries section size, 8) \|\| u64 \|\| '''Entry offsets section size'''
	\|-		\|-
	\| Y + 8 \|\| u32[...] \|\| '''Entry offsets''' (relative to the Entries section)		\| Y + 8 \|\| u32[...] \|\| '''Entry offsets''' (relative to the Entries section)
	\|-		\|-
	\| Z = align(Y + entry offset section size, 8) \|\| u64 \|\| Data section size		\| Z = align(Y + entry offset section size, 8) \|\| u64 \|\| '''Data section size'''
	\|-		\|-
	\| Z + 8 \|\| any \|\| '''Data'''		\| Z + 8 \|\| any \|\| '''Data'''
	\|-		\|-
	\| A = align(Z + data section size, 4) \|\| u32 \|\| ~~Name~~ section size		\| A = align(Z + data section size, 4) \|\| u32 \|\| '''Names section size'''
	\|-		\|-
	\| A + 4 \|\| C strings \|\| '''Names'''		\| A + 4 \|\| C strings \|\| '''Names'''

imported>Leoetlino: /* Entry */

2020-04-17T13:57:14Z

Entry

← Older revision		Revision as of 13:57, 17 April 2020
Line 54:		Line 54:
	\|-		\|-
	\| 0x0 \|\| u16 \|\| '''Node index''' if this describes a FixedHash child node (if so, it must be <= 0xFFED)		\| 0x0 \|\| u16 \|\| '''Node index''' if this describes a FixedHash child node (if so, it must be <= 0xFFED)

			Otherwise, must be >= 0xFFF0 for non-node data.
	\|-		\|-
	\| 0x2 \|\| u16 \|\| '''Name offset''' (relative to the Name section)		\| 0x2 \|\| u16 \|\| '''Name offset''' (relative to the Name section)

imported>Leoetlino: /* Format */ Entry

2020-04-16T20:48:02Z

Format: Entry

@@ Line 29: / Line 29: @@
 | 0x6 || u16 || Padding? {{check}}
 |-
-| 0x8 || u32[N + 1] || '''Offsets to the first entry in each bucket''' (relative to the Entries section)
+| 0x8 || u32[N + 1] || '''Offsets to the first entry in each bucket''' (relative to the Entries section)<br>0xFFFFFFFF for empty buckets.
 |-
 | X = (0x8 + 4*(N+1) + 3) & -8 || u64 || Entries section size
@@ Line 49: / Line 49: @@
 |}
 [[Category:File formats]]

imported>Leoetlino: /* Format */ alignment

2020-04-16T20:42:48Z

Format: alignment

← Older revision		Revision as of 20:42, 16 April 2020
Line 35:		Line 35:
	\| X + 8 \|\| Entry[...] \|\| '''Entries'''		\| X + 8 \|\| Entry[...] \|\| '''Entries'''
	\|-		\|-
	\| Y = X + entries section size \|\| u64 \|\| Entry offsets section size		\| Y = align(X + entries section size, 8) \|\| u64 \|\| Entry offsets section size
	\|-		\|-
	\| Y + 8 \|\| u32[...] \|\| '''Entry offsets''' (relative to the Entries section)		\| Y + 8 \|\| u32[...] \|\| '''Entry offsets''' (relative to the Entries section)
	\|-		\|-
	\| Z = Y + entry offset section size \|\| u64 \|\| Data section size		\| Z = align(Y + entry offset section size, 8) \|\| u64 \|\| Data section size
	\|-		\|-
	\| Z + 8 \|\| any \|\| '''Data'''		\| Z + 8 \|\| any \|\| '''Data'''
	\|-		\|-
	\| A = Z + data section size \|\| u32 \|\| Name section size		\| A = align(Z + data section size, 4) \|\| u32 \|\| Name section size
	\|-		\|-
	\| A + 4 \|\| C strings \|\| '''Names'''		\| A + 4 \|\| C strings \|\| '''Names'''

imported>Leoetlino: Created page with "{{File format|name=FixedHash|version=1|endianness=little}} '''FixedHash''' is a custom Grezzo format for serializing wikipedia:hash table|s that map string keys to arbitra..."

2020-04-16T20:42:04Z

Created page with "{{File format|name=FixedHash|version=1|endianness=little}} '''FixedHash''' is a custom Grezzo format for serializing wikipedia:hash tables that map string keys to arbitra..."

New page

{{File format|name=FixedHash|version=1|endianness=little}}
'''FixedHash''' is a custom Grezzo format for serializing [[wikipedia:hash table|hash table]]s that map string keys to arbitrary binary blobs.

== Hash function ==
String keys are hashed using the following hash function:

<source lang="c++">
u32 Hash(const char* key) {
u32 hash = 0;
while (*key) {
hash ^= *key++ + (h >> 2) + (h << 5);
}
return hash;
}
</source>

== Format ==
{|class="wikitable"
! Offset !! Type !! Description
|-
| 0x0 || u8 || '''Magic''' (must be 0x3D)
|-
| 0x1 || u8 || '''Version''' (must be 1)
|-
| 0x2 || u16 || '''Number of hash table buckets''' (N)
|-
| 0x4 || u16 || '''Number of child FixedHash nodes'''
|-
| 0x6 || u16 || Padding? {{check}}
|-
| 0x8 || u32[N + 1] || '''Offsets to the first entry in each bucket''' (relative to the Entries section)
|-
| X = (0x8 + 4*(N+1) + 3) & -8 || u64 || Entries section size
|-
| X + 8 || Entry[...] || '''Entries'''
|-
| Y = X + entries section size || u64 || Entry offsets section size
|-
| Y + 8 || u32[...] || '''Entry offsets''' (relative to the Entries section)
|-
| Z = Y + entry offset section size || u64 || Data section size
|-
| Z + 8 || any || '''Data'''
|-
| A = Z + data section size || u32 || Name section size
|-
| A + 4 || C strings || '''Names'''
|-
|}

[[Category:File formats]]