##// END OF EJS Templates
merge: store commitinfo if these is a dc or cd conflict...
merge: store commitinfo if these is a dc or cd conflict delete-changed or changed-delete conflicts can either be resolved by mergetool, if some tool is passed and using or by user choose something on prompt or user doing some `hg revert` after choosing the file to remain conflicted. If the user decides to keep the changed side, on commit we just reuse the parent filenode. This is mostly fine unless we are in a distributed environment and people are doing criss-cross merges. Since, we don't have recursive merges or any other way of describing the end result of the merge was an explicit choice and it should be differentiated from it's ancestors, merge algo during criss-cross merges fails to take in account the explicit choice made by user and end up with a what-can-be-said-wrong-merge. The solution which we are trying to fix this is by creating a filenode on commit instead of reusing the parent filenode. This helps differentiate between pre-merged filenode and post-merge filenode and kind of tells about the choice user made. To implement creating new filenode functionality, we store info about these files in mergestate so that we can read them on commit and force create a new filenode. Differential Revision: https://phab.mercurial-scm.org/D8988

File last commit:

r45916:27424779 default
r46158:4c8a93ec default
Show More
parsers.rs
444 lines | 14.0 KiB | application/rls-services+xml | RustLexer
// Copyright 2019 Raphaël Gomès <rgomes@octobus.net>
//
// This software may be used and distributed according to the terms of the
// GNU General Public License version 2 or any later version.
use crate::utils::hg_path::HgPath;
use crate::{
dirstate::{CopyMap, EntryState, StateMap},
DirstateEntry, DirstatePackError, DirstateParents, DirstateParseError,
};
use byteorder::{BigEndian, ReadBytesExt, WriteBytesExt};
use micro_timer::timed;
use std::convert::{TryFrom, TryInto};
use std::io::Cursor;
use std::time::Duration;
/// Parents are stored in the dirstate as byte hashes.
pub const PARENT_SIZE: usize = 20;
/// Dirstate entries have a static part of 8 + 32 + 32 + 32 + 32 bits.
const MIN_ENTRY_SIZE: usize = 17;
type ParseResult<'a> = (
DirstateParents,
Vec<(&'a HgPath, DirstateEntry)>,
Vec<(&'a HgPath, &'a HgPath)>,
);
#[timed]
pub fn parse_dirstate(
contents: &[u8],
) -> Result<ParseResult, DirstateParseError> {
if contents.len() < PARENT_SIZE * 2 {
return Err(DirstateParseError::TooLittleData);
}
let mut copies = vec![];
let mut entries = vec![];
let mut curr_pos = PARENT_SIZE * 2;
let parents = DirstateParents {
p1: contents[..PARENT_SIZE].try_into().unwrap(),
p2: contents[PARENT_SIZE..curr_pos].try_into().unwrap(),
};
while curr_pos < contents.len() {
if curr_pos + MIN_ENTRY_SIZE > contents.len() {
return Err(DirstateParseError::Overflow);
}
let entry_bytes = &contents[curr_pos..];
let mut cursor = Cursor::new(entry_bytes);
let state = EntryState::try_from(cursor.read_u8()?)?;
let mode = cursor.read_i32::<BigEndian>()?;
let size = cursor.read_i32::<BigEndian>()?;
let mtime = cursor.read_i32::<BigEndian>()?;
let path_len = cursor.read_i32::<BigEndian>()? as usize;
if path_len > contents.len() - curr_pos {
return Err(DirstateParseError::Overflow);
}
// Slice instead of allocating a Vec needed for `read_exact`
let path = &entry_bytes[MIN_ENTRY_SIZE..MIN_ENTRY_SIZE + (path_len)];
let (path, copy) = match memchr::memchr(0, path) {
None => (path, None),
Some(i) => (&path[..i], Some(&path[(i + 1)..])),
};
if let Some(copy_path) = copy {
copies.push((HgPath::new(path), HgPath::new(copy_path)));
};
entries.push((
HgPath::new(path),
DirstateEntry {
state,
mode,
size,
mtime,
},
));
curr_pos = curr_pos + MIN_ENTRY_SIZE + (path_len);
}
Ok((parents, entries, copies))
}
/// `now` is the duration in seconds since the Unix epoch
pub fn pack_dirstate(
state_map: &mut StateMap,
copy_map: &CopyMap,
parents: DirstateParents,
now: Duration,
) -> Result<Vec<u8>, DirstatePackError> {
// TODO move away from i32 before 2038.
let now: i32 = now.as_secs().try_into().expect("time overflow");
let expected_size: usize = state_map
.iter()
.map(|(filename, _)| {
let mut length = MIN_ENTRY_SIZE + filename.len();
if let Some(copy) = copy_map.get(filename) {
length += copy.len() + 1;
}
length
})
.sum();
let expected_size = expected_size + PARENT_SIZE * 2;
let mut packed = Vec::with_capacity(expected_size);
let mut new_state_map = vec![];
packed.extend(&parents.p1);
packed.extend(&parents.p2);
for (filename, entry) in state_map.iter() {
let new_filename = filename.to_owned();
let mut new_mtime: i32 = entry.mtime;
if entry.state == EntryState::Normal && entry.mtime == now {
// The file was last modified "simultaneously" with the current
// write to dirstate (i.e. within the same second for file-
// systems with a granularity of 1 sec). This commonly happens
// for at least a couple of files on 'update'.
// The user could change the file without changing its size
// within the same second. Invalidate the file's mtime in
// dirstate, forcing future 'status' calls to compare the
// contents of the file if the size is the same. This prevents
// mistakenly treating such files as clean.
new_mtime = -1;
new_state_map.push((
filename.to_owned(),
DirstateEntry {
mtime: new_mtime,
..*entry
},
));
}
let mut new_filename = new_filename.into_vec();
if let Some(copy) = copy_map.get(filename) {
new_filename.push(b'\0');
new_filename.extend(copy.bytes());
}
packed.write_u8(entry.state.into())?;
packed.write_i32::<BigEndian>(entry.mode)?;
packed.write_i32::<BigEndian>(entry.size)?;
packed.write_i32::<BigEndian>(new_mtime)?;
packed.write_i32::<BigEndian>(new_filename.len() as i32)?;
packed.extend(new_filename)
}
if packed.len() != expected_size {
return Err(DirstatePackError::BadSize(expected_size, packed.len()));
}
state_map.extend(new_state_map);
Ok(packed)
}
#[cfg(test)]
mod tests {
use super::*;
use crate::{utils::hg_path::HgPathBuf, FastHashMap};
#[test]
fn test_pack_dirstate_empty() {
let mut state_map: StateMap = FastHashMap::default();
let copymap = FastHashMap::default();
let parents = DirstateParents {
p1: *b"12345678910111213141",
p2: *b"00000000000000000000",
};
let now = Duration::new(15000000, 0);
let expected = b"1234567891011121314100000000000000000000".to_vec();
assert_eq!(
expected,
pack_dirstate(&mut state_map, &copymap, parents, now).unwrap()
);
assert!(state_map.is_empty())
}
#[test]
fn test_pack_dirstate_one_entry() {
let expected_state_map: StateMap = [(
HgPathBuf::from_bytes(b"f1"),
DirstateEntry {
state: EntryState::Normal,
mode: 0o644,
size: 0,
mtime: 791231220,
},
)]
.iter()
.cloned()
.collect();
let mut state_map = expected_state_map.clone();
let copymap = FastHashMap::default();
let parents = DirstateParents {
p1: *b"12345678910111213141",
p2: *b"00000000000000000000",
};
let now = Duration::new(15000000, 0);
let expected = [
49, 50, 51, 52, 53, 54, 55, 56, 57, 49, 48, 49, 49, 49, 50, 49,
51, 49, 52, 49, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48,
48, 48, 48, 48, 48, 48, 48, 48, 110, 0, 0, 1, 164, 0, 0, 0, 0, 47,
41, 58, 244, 0, 0, 0, 2, 102, 49,
]
.to_vec();
assert_eq!(
expected,
pack_dirstate(&mut state_map, &copymap, parents, now).unwrap()
);
assert_eq!(expected_state_map, state_map);
}
#[test]
fn test_pack_dirstate_one_entry_with_copy() {
let expected_state_map: StateMap = [(
HgPathBuf::from_bytes(b"f1"),
DirstateEntry {
state: EntryState::Normal,
mode: 0o644,
size: 0,
mtime: 791231220,
},
)]
.iter()
.cloned()
.collect();
let mut state_map = expected_state_map.clone();
let mut copymap = FastHashMap::default();
copymap.insert(
HgPathBuf::from_bytes(b"f1"),
HgPathBuf::from_bytes(b"copyname"),
);
let parents = DirstateParents {
p1: *b"12345678910111213141",
p2: *b"00000000000000000000",
};
let now = Duration::new(15000000, 0);
let expected = [
49, 50, 51, 52, 53, 54, 55, 56, 57, 49, 48, 49, 49, 49, 50, 49,
51, 49, 52, 49, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48, 48,
48, 48, 48, 48, 48, 48, 48, 48, 110, 0, 0, 1, 164, 0, 0, 0, 0, 47,
41, 58, 244, 0, 0, 0, 11, 102, 49, 0, 99, 111, 112, 121, 110, 97,
109, 101,
]
.to_vec();
assert_eq!(
expected,
pack_dirstate(&mut state_map, &copymap, parents, now).unwrap()
);
assert_eq!(expected_state_map, state_map);
}
#[test]
fn test_parse_pack_one_entry_with_copy() {
let mut state_map: StateMap = [(
HgPathBuf::from_bytes(b"f1"),
DirstateEntry {
state: EntryState::Normal,
mode: 0o644,
size: 0,
mtime: 791231220,
},
)]
.iter()
.cloned()
.collect();
let mut copymap = FastHashMap::default();
copymap.insert(
HgPathBuf::from_bytes(b"f1"),
HgPathBuf::from_bytes(b"copyname"),
);
let parents = DirstateParents {
p1: *b"12345678910111213141",
p2: *b"00000000000000000000",
};
let now = Duration::new(15000000, 0);
let result =
pack_dirstate(&mut state_map, &copymap, parents.clone(), now)
.unwrap();
let (new_parents, entries, copies) =
parse_dirstate(result.as_slice()).unwrap();
let new_state_map: StateMap = entries
.into_iter()
.map(|(path, entry)| (path.to_owned(), entry))
.collect();
let new_copy_map: CopyMap = copies
.into_iter()
.map(|(path, copy)| (path.to_owned(), copy.to_owned()))
.collect();
assert_eq!(
(parents, state_map, copymap),
(new_parents, new_state_map, new_copy_map)
)
}
#[test]
fn test_parse_pack_multiple_entries_with_copy() {
let mut state_map: StateMap = [
(
HgPathBuf::from_bytes(b"f1"),
DirstateEntry {
state: EntryState::Normal,
mode: 0o644,
size: 0,
mtime: 791231220,
},
),
(
HgPathBuf::from_bytes(b"f2"),
DirstateEntry {
state: EntryState::Merged,
mode: 0o777,
size: 1000,
mtime: 791231220,
},
),
(
HgPathBuf::from_bytes(b"f3"),
DirstateEntry {
state: EntryState::Removed,
mode: 0o644,
size: 234553,
mtime: 791231220,
},
),
(
HgPathBuf::from_bytes(b"f4\xF6"),
DirstateEntry {
state: EntryState::Added,
mode: 0o644,
size: -1,
mtime: -1,
},
),
]
.iter()
.cloned()
.collect();
let mut copymap = FastHashMap::default();
copymap.insert(
HgPathBuf::from_bytes(b"f1"),
HgPathBuf::from_bytes(b"copyname"),
);
copymap.insert(
HgPathBuf::from_bytes(b"f4\xF6"),
HgPathBuf::from_bytes(b"copyname2"),
);
let parents = DirstateParents {
p1: *b"12345678910111213141",
p2: *b"00000000000000000000",
};
let now = Duration::new(15000000, 0);
let result =
pack_dirstate(&mut state_map, &copymap, parents.clone(), now)
.unwrap();
let (new_parents, entries, copies) =
parse_dirstate(result.as_slice()).unwrap();
let new_state_map: StateMap = entries
.into_iter()
.map(|(path, entry)| (path.to_owned(), entry))
.collect();
let new_copy_map: CopyMap = copies
.into_iter()
.map(|(path, copy)| (path.to_owned(), copy.to_owned()))
.collect();
assert_eq!(
(parents, state_map, copymap),
(new_parents, new_state_map, new_copy_map)
)
}
#[test]
/// https://www.mercurial-scm.org/repo/hg/rev/af3f26b6bba4
fn test_parse_pack_one_entry_with_copy_and_time_conflict() {
let mut state_map: StateMap = [(
HgPathBuf::from_bytes(b"f1"),
DirstateEntry {
state: EntryState::Normal,
mode: 0o644,
size: 0,
mtime: 15000000,
},
)]
.iter()
.cloned()
.collect();
let mut copymap = FastHashMap::default();
copymap.insert(
HgPathBuf::from_bytes(b"f1"),
HgPathBuf::from_bytes(b"copyname"),
);
let parents = DirstateParents {
p1: *b"12345678910111213141",
p2: *b"00000000000000000000",
};
let now = Duration::new(15000000, 0);
let result =
pack_dirstate(&mut state_map, &copymap, parents.clone(), now)
.unwrap();
let (new_parents, entries, copies) =
parse_dirstate(result.as_slice()).unwrap();
let new_state_map: StateMap = entries
.into_iter()
.map(|(path, entry)| (path.to_owned(), entry))
.collect();
let new_copy_map: CopyMap = copies
.into_iter()
.map(|(path, copy)| (path.to_owned(), copy.to_owned()))
.collect();
assert_eq!(
(
parents,
[(
HgPathBuf::from_bytes(b"f1"),
DirstateEntry {
state: EntryState::Normal,
mode: 0o644,
size: 0,
mtime: -1
}
)]
.iter()
.cloned()
.collect::<StateMap>(),
copymap,
),
(new_parents, new_state_map, new_copy_map)
)
}
}