diff options
Diffstat (limited to 'src')
| -rwxr-xr-x | src/cargo-meson.sh | 32 | ||||
| -rw-r--r-- | src/lib.rs | 1 | ||||
| -rw-r--r-- | src/meson.build | 41 | ||||
| -rw-r--r-- | src/varint.rs | 92 |
4 files changed, 166 insertions, 0 deletions
diff --git a/src/cargo-meson.sh b/src/cargo-meson.sh new file mode 100755 index 0000000000..99400986d9 --- /dev/null +++ b/src/cargo-meson.sh @@ -0,0 +1,32 @@ +#!/bin/sh + +if test "$#" -lt 2 +then + exit 1 +fi + +SOURCE_DIR="$1" +BUILD_DIR="$2" +BUILD_TYPE=debug + +shift 2 + +for arg +do + case "$arg" in + --release) + BUILD_TYPE=release;; + esac +done + +cargo build --lib --quiet --manifest-path="$SOURCE_DIR/Cargo.toml" --target-dir="$BUILD_DIR" "$@" +RET=$? +if test $RET -ne 0 +then + exit $RET +fi + +if ! cmp "$BUILD_DIR/$BUILD_TYPE/libgitcore.a" "$BUILD_DIR/libgitcore.a" >/dev/null 2>&1 +then + cp "$BUILD_DIR/$BUILD_TYPE/libgitcore.a" "$BUILD_DIR/libgitcore.a" +fi diff --git a/src/lib.rs b/src/lib.rs new file mode 100644 index 0000000000..9da70d8b57 --- /dev/null +++ b/src/lib.rs @@ -0,0 +1 @@ +pub mod varint; diff --git a/src/meson.build b/src/meson.build new file mode 100644 index 0000000000..25b9ad5a14 --- /dev/null +++ b/src/meson.build @@ -0,0 +1,41 @@ +libgit_rs_sources = [ + 'lib.rs', + 'varint.rs', +] + +# Unfortunately we must use a wrapper command to move the output file into the +# current build directory. This can fixed once `cargo build --artifact-dir` +# stabilizes. See https://github.com/rust-lang/cargo/issues/6790 for that +# effort. +cargo_command = [ + shell, + meson.current_source_dir() / 'cargo-meson.sh', + meson.project_source_root(), + meson.current_build_dir(), +] +if get_option('buildtype') == 'release' + cargo_command += '--release' +endif + +libgit_rs = custom_target('git_rs', + input: libgit_rs_sources + [ + meson.project_source_root() / 'Cargo.toml', + ], + output: 'libgitcore.a', + command: cargo_command, +) +libgit_dependencies += declare_dependency(link_with: libgit_rs) + +if get_option('tests') + test('rust', cargo, + args: [ + 'test', + '--manifest-path', + meson.project_source_root() / 'Cargo.toml', + '--target-dir', + meson.current_build_dir() / 'target', + ], + timeout: 0, + protocol: 'rust', + ) +endif diff --git a/src/varint.rs b/src/varint.rs new file mode 100644 index 0000000000..6e610bdd8e --- /dev/null +++ b/src/varint.rs @@ -0,0 +1,92 @@ +#[no_mangle] +pub unsafe extern "C" fn decode_varint(bufp: *mut *const u8) -> u64 { + let mut buf = *bufp; + let mut c = *buf; + let mut val = u64::from(c & 127); + + buf = buf.add(1); + + while (c & 128) != 0 { + val = val.wrapping_add(1); + if val == 0 || val.leading_zeros() < 7 { + return 0; // overflow + } + + c = *buf; + buf = buf.add(1); + + val = (val << 7) + u64::from(c & 127); + } + + *bufp = buf; + val +} + +#[no_mangle] +pub unsafe extern "C" fn encode_varint(value: u64, buf: *mut u8) -> u8 { + let mut varint: [u8; 16] = [0; 16]; + let mut pos = varint.len() - 1; + + varint[pos] = (value & 127) as u8; + + let mut value = value >> 7; + while value != 0 { + pos -= 1; + value -= 1; + varint[pos] = 128 | (value & 127) as u8; + value >>= 7; + } + + if !buf.is_null() { + std::ptr::copy_nonoverlapping(varint.as_ptr().add(pos), buf, varint.len() - pos); + } + + (varint.len() - pos) as u8 +} + +#[cfg(test)] +mod tests { + use super::*; + + #[test] + fn test_decode_varint() { + unsafe { + assert_eq!(decode_varint(&mut [0x00].as_slice().as_ptr()), 0); + assert_eq!(decode_varint(&mut [0x01].as_slice().as_ptr()), 1); + assert_eq!(decode_varint(&mut [0x7f].as_slice().as_ptr()), 127); + assert_eq!(decode_varint(&mut [0x80, 0x00].as_slice().as_ptr()), 128); + assert_eq!(decode_varint(&mut [0x80, 0x01].as_slice().as_ptr()), 129); + assert_eq!(decode_varint(&mut [0x80, 0x7f].as_slice().as_ptr()), 255); + + // Overflows are expected to return 0. + assert_eq!(decode_varint(&mut [0x88; 16].as_slice().as_ptr()), 0); + } + } + + #[test] + fn test_encode_varint() { + unsafe { + let mut varint: [u8; 16] = [0; 16]; + + assert_eq!(encode_varint(0, std::ptr::null_mut()), 1); + + assert_eq!(encode_varint(0, varint.as_mut_slice().as_mut_ptr()), 1); + assert_eq!(varint, [0; 16]); + + assert_eq!(encode_varint(10, varint.as_mut_slice().as_mut_ptr()), 1); + assert_eq!(varint, [10, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]); + + assert_eq!(encode_varint(127, varint.as_mut_slice().as_mut_ptr()), 1); + assert_eq!(varint, [127, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]); + + assert_eq!(encode_varint(128, varint.as_mut_slice().as_mut_ptr()), 2); + assert_eq!(varint, [128, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]); + + assert_eq!(encode_varint(129, varint.as_mut_slice().as_mut_ptr()), 2); + assert_eq!(varint, [128, 1, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]); + + assert_eq!(encode_varint(255, varint.as_mut_slice().as_mut_ptr()), 2); + assert_eq!(varint, [128, 127, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0]); + } + } +} |