WIP: Replace unsafe code with ouroboros in db #771
5 changed files with 194 additions and 109 deletions
57
Cargo.lock
generated
57
Cargo.lock
generated
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@ -74,6 +74,12 @@ dependencies = [
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"memchr",
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]
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[[package]]
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name = "aliasable"
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version = "0.1.3"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "250f629c0161ad8107cf89319e990051fae62832fd343083bea452d93e2205fd"
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[[package]]
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name = "allocator-api2"
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version = "0.2.16"
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@ -1443,6 +1449,7 @@ dependencies = [
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"heed",
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"hexdump",
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"mktemp",
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"ouroboros",
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"rusqlite",
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"tracing",
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]
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@ -2775,6 +2782,31 @@ dependencies = [
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"num-traits",
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]
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[[package]]
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name = "ouroboros"
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version = "0.18.3"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "97b7be5a8a3462b752f4be3ff2b2bf2f7f1d00834902e46be2a4d68b87b0573c"
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dependencies = [
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"aliasable",
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"ouroboros_macro",
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"static_assertions",
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]
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[[package]]
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name = "ouroboros_macro"
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version = "0.18.3"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "b645dcde5f119c2c454a92d0dfa271a2a3b205da92e4292a68ead4bdbfde1f33"
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dependencies = [
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"heck 0.4.1",
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"itertools 0.12.1",
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"proc-macro2",
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"proc-macro2-diagnostics",
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"quote",
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"syn 2.0.48",
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]
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[[package]]
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name = "outref"
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version = "0.5.1"
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@ -3102,6 +3134,19 @@ dependencies = [
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"unicode-ident",
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]
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[[package]]
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name = "proc-macro2-diagnostics"
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version = "0.10.1"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "af066a9c399a26e020ada66a034357a868728e72cd426f3adcd35f80d88d88c8"
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dependencies = [
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"proc-macro2",
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"quote",
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"syn 2.0.48",
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"version_check",
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"yansi",
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]
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[[package]]
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name = "prometheus"
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version = "0.13.3"
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@ -3834,6 +3879,12 @@ dependencies = [
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"der",
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]
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[[package]]
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name = "static_assertions"
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version = "1.1.0"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"
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[[package]]
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name = "static_init"
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version = "1.0.3"
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@ -4844,6 +4895,12 @@ version = "0.8.8"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "53be06678ed9e83edb1745eb72efc0bbcd7b5c3c35711a860906aed827a13d61"
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[[package]]
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name = "yansi"
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version = "1.0.0"
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source = "registry+https://github.com/rust-lang/crates.io-index"
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checksum = "6c2861d76f58ec8fc95708b9b1e417f7b12fd72ad33c01fa6886707092dea0d3"
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[[package]]
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name = "zerocopy"
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version = "0.7.32"
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90
Cargo.nix
90
Cargo.nix
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@ -34,7 +34,7 @@ args@{
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ignoreLockHash,
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}:
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let
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nixifiedLockHash = "23e1504df44ec18cfc5c872c858154304c16da2a6c1f7c9f06608ef833815f30";
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nixifiedLockHash = "17e620fad07e725e301488a3746ca3512d8785ce3077f634adde82e9e4eab2bb";
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workspaceSrc = if args.workspaceSrc == null then ./. else args.workspaceSrc;
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currentLockHash = builtins.hashFile "sha256" (workspaceSrc + /Cargo.lock);
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lockHashIgnored = if ignoreLockHash
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@ -176,6 +176,17 @@ in
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};
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});
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"registry+https://github.com/rust-lang/crates.io-index".aliasable."0.1.3" = overridableMkRustCrate (profileName: rec {
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name = "aliasable";
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version = "0.1.3";
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registry = "registry+https://github.com/rust-lang/crates.io-index";
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src = fetchCratesIo { inherit name version; sha256 = "250f629c0161ad8107cf89319e990051fae62832fd343083bea452d93e2205fd"; };
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features = builtins.concatLists [
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[ "alloc" ]
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[ "default" ]
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];
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});
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"registry+https://github.com/rust-lang/crates.io-index".allocator-api2."0.2.16" = overridableMkRustCrate (profileName: rec {
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name = "allocator-api2";
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version = "0.2.16";
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@ -2095,6 +2106,7 @@ in
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err_derive = (buildRustPackages."registry+https://github.com/rust-lang/crates.io-index".err-derive."0.3.1" { profileName = "__noProfile"; }).out;
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${ if rootFeatures' ? "garage/default" || rootFeatures' ? "garage/lmdb" || rootFeatures' ? "garage_db/default" || rootFeatures' ? "garage_db/heed" || rootFeatures' ? "garage_db/lmdb" || rootFeatures' ? "garage_model/default" || rootFeatures' ? "garage_model/lmdb" then "heed" else null } = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".heed."0.11.0" { inherit profileName; }).out;
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hexdump = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".hexdump."0.1.1" { inherit profileName; }).out;
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ouroboros = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".ouroboros."0.18.3" { inherit profileName; }).out;
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${ if rootFeatures' ? "garage/bundled-libs" || rootFeatures' ? "garage/default" || rootFeatures' ? "garage/sqlite" || rootFeatures' ? "garage_db/bundled-libs" || rootFeatures' ? "garage_db/default" || rootFeatures' ? "garage_db/rusqlite" || rootFeatures' ? "garage_db/sqlite" || rootFeatures' ? "garage_model/default" || rootFeatures' ? "garage_model/sqlite" then "rusqlite" else null } = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".rusqlite."0.30.0" { inherit profileName; }).out;
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tracing = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".tracing."0.1.40" { inherit profileName; }).out;
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};
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@ -2510,7 +2522,7 @@ in
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registry = "registry+https://github.com/rust-lang/crates.io-index";
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src = fetchCratesIo { inherit name version; sha256 = "95505c38b4572b2d910cecb0281560f54b440a19336cbbcb27bf6ce6adc6f5a8"; };
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features = builtins.concatLists [
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(lib.optional (rootFeatures' ? "k2v-client/clap" || rootFeatures' ? "k2v-client/cli") "default")
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[ "default" ]
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];
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});
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@ -3958,6 +3970,40 @@ in
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};
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});
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"registry+https://github.com/rust-lang/crates.io-index".ouroboros."0.18.3" = overridableMkRustCrate (profileName: rec {
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name = "ouroboros";
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version = "0.18.3";
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registry = "registry+https://github.com/rust-lang/crates.io-index";
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src = fetchCratesIo { inherit name version; sha256 = "97b7be5a8a3462b752f4be3ff2b2bf2f7f1d00834902e46be2a4d68b87b0573c"; };
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features = builtins.concatLists [
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[ "default" ]
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[ "std" ]
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];
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dependencies = {
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aliasable = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".aliasable."0.1.3" { inherit profileName; }).out;
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ouroboros_macro = (buildRustPackages."registry+https://github.com/rust-lang/crates.io-index".ouroboros_macro."0.18.3" { profileName = "__noProfile"; }).out;
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static_assertions = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".static_assertions."1.1.0" { inherit profileName; }).out;
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};
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});
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"registry+https://github.com/rust-lang/crates.io-index".ouroboros_macro."0.18.3" = overridableMkRustCrate (profileName: rec {
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name = "ouroboros_macro";
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version = "0.18.3";
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registry = "registry+https://github.com/rust-lang/crates.io-index";
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src = fetchCratesIo { inherit name version; sha256 = "b645dcde5f119c2c454a92d0dfa271a2a3b205da92e4292a68ead4bdbfde1f33"; };
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features = builtins.concatLists [
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[ "std" ]
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];
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dependencies = {
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heck = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".heck."0.4.1" { inherit profileName; }).out;
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itertools = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".itertools."0.12.1" { inherit profileName; }).out;
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proc_macro2 = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".proc-macro2."1.0.78" { inherit profileName; }).out;
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proc_macro2_diagnostics = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".proc-macro2-diagnostics."0.10.1" { inherit profileName; }).out;
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quote = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".quote."1.0.35" { inherit profileName; }).out;
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syn = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".syn."2.0.48" { inherit profileName; }).out;
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};
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});
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"registry+https://github.com/rust-lang/crates.io-index".outref."0.5.1" = overridableMkRustCrate (profileName: rec {
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name = "outref";
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version = "0.5.1";
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@ -4394,6 +4440,27 @@ in
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};
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});
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"registry+https://github.com/rust-lang/crates.io-index".proc-macro2-diagnostics."0.10.1" = overridableMkRustCrate (profileName: rec {
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name = "proc-macro2-diagnostics";
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version = "0.10.1";
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registry = "registry+https://github.com/rust-lang/crates.io-index";
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src = fetchCratesIo { inherit name version; sha256 = "af066a9c399a26e020ada66a034357a868728e72cd426f3adcd35f80d88d88c8"; };
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features = builtins.concatLists [
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[ "colors" ]
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[ "default" ]
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[ "yansi" ]
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];
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dependencies = {
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proc_macro2 = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".proc-macro2."1.0.78" { inherit profileName; }).out;
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quote = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".quote."1.0.35" { inherit profileName; }).out;
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syn = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".syn."2.0.48" { inherit profileName; }).out;
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yansi = (rustPackages."registry+https://github.com/rust-lang/crates.io-index".yansi."1.0.0" { inherit profileName; }).out;
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};
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buildDependencies = {
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version_check = (buildRustPackages."registry+https://github.com/rust-lang/crates.io-index".version_check."0.9.4" { profileName = "__noProfile"; }).out;
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};
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});
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"registry+https://github.com/rust-lang/crates.io-index".prometheus."0.13.3" = overridableMkRustCrate (profileName: rec {
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name = "prometheus";
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version = "0.13.3";
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@ -5466,6 +5533,13 @@ in
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};
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});
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"registry+https://github.com/rust-lang/crates.io-index".static_assertions."1.1.0" = overridableMkRustCrate (profileName: rec {
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name = "static_assertions";
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version = "1.1.0";
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registry = "registry+https://github.com/rust-lang/crates.io-index";
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src = fetchCratesIo { inherit name version; sha256 = "a2eb9349b6444b326872e140eb1cf5e7c522154d69e7a0ffb0fb81c06b37543f"; };
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});
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"registry+https://github.com/rust-lang/crates.io-index".static_init."1.0.3" = overridableMkRustCrate (profileName: rec {
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name = "static_init";
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version = "1.0.3";
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@ -6957,6 +7031,18 @@ in
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];
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});
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"registry+https://github.com/rust-lang/crates.io-index".yansi."1.0.0" = overridableMkRustCrate (profileName: rec {
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name = "yansi";
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version = "1.0.0";
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registry = "registry+https://github.com/rust-lang/crates.io-index";
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src = fetchCratesIo { inherit name version; sha256 = "6c2861d76f58ec8fc95708b9b1e417f7b12fd72ad33c01fa6886707092dea0d3"; };
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features = builtins.concatLists [
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[ "alloc" ]
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[ "default" ]
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[ "std" ]
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];
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});
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"registry+https://github.com/rust-lang/crates.io-index".zerocopy."0.7.32" = overridableMkRustCrate (profileName: rec {
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name = "zerocopy";
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version = "0.7.32";
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|
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@ -58,6 +58,7 @@ md-5 = "0.10"
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mktemp = "0.5"
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nix = { version = "0.27", default-features = false, features = ["fs"] }
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nom = "7.1"
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ouroboros = "0.18"
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parse_duration = "2.1"
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pin-project = "1.0.12"
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pnet_datalink = "0.34"
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|
|
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@ -14,6 +14,7 @@ path = "lib.rs"
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[dependencies]
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err-derive.workspace = true
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hexdump.workspace = true
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ouroboros.workspace = true
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tracing.workspace = true
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heed = { workspace = true, optional = true }
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|
|
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@ -1,11 +1,9 @@
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use core::ops::Bound;
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use std::borrow::BorrowMut;
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use std::marker::PhantomPinned;
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use std::pin::Pin;
|
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use std::ptr::NonNull;
|
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use std::sync::{Arc, Mutex, MutexGuard};
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use ouroboros::self_referencing;
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use rusqlite::{params, Connection, Rows, Statement, Transaction};
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use crate::{
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|
|
@ -197,7 +195,7 @@ impl IDb for SqliteDb {
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|||
|
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let tree = this.get_tree(tree)?;
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let sql = format!("SELECT k, v FROM {} ORDER BY k ASC", tree);
|
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DbValueIterator::make(this, &sql, [])
|
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make_iterator(this, &sql, [])
|
||||
}
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fn iter_rev(&self, tree: usize) -> Result<ValueIter<'_>> {
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|
|
@ -207,7 +205,7 @@ impl IDb for SqliteDb {
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|||
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let tree = this.get_tree(tree)?;
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let sql = format!("SELECT k, v FROM {} ORDER BY k DESC", tree);
|
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DbValueIterator::make(this, &sql, [])
|
||||
make_iterator(this, &sql, [])
|
||||
}
|
||||
|
||||
fn range<'r>(
|
||||
|
|
@ -230,7 +228,7 @@ impl IDb for SqliteDb {
|
|||
.map(|x| x as &dyn rusqlite::ToSql)
|
||||
.collect::<Vec<_>>();
|
||||
|
||||
DbValueIterator::make::<&[&dyn rusqlite::ToSql]>(this, &sql, params.as_ref())
|
||||
make_iterator::<&[&dyn rusqlite::ToSql]>(this, &sql, params.as_ref())
|
||||
}
|
||||
fn range_rev<'r>(
|
||||
&self,
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||||
|
|
@ -252,7 +250,7 @@ impl IDb for SqliteDb {
|
|||
.map(|x| x as &dyn rusqlite::ToSql)
|
||||
.collect::<Vec<_>>();
|
||||
|
||||
DbValueIterator::make::<&[&dyn rusqlite::ToSql]>(this, &sql, params.as_ref())
|
||||
make_iterator::<&[&dyn rusqlite::ToSql]>(this, &sql, params.as_ref())
|
||||
}
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||||
|
||||
// ----
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||||
|
|
@ -372,12 +370,12 @@ impl<'a> ITx for SqliteTx<'a> {
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|||
fn iter(&self, tree: usize) -> TxOpResult<TxValueIter<'_>> {
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||||
let tree = self.get_tree(tree)?;
|
||||
let sql = format!("SELECT k, v FROM {} ORDER BY k ASC", tree);
|
||||
TxValueIterator::make(self, &sql, [])
|
||||
make_tx_iterator(self, &sql, [])
|
||||
}
|
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fn iter_rev(&self, tree: usize) -> TxOpResult<TxValueIter<'_>> {
|
||||
let tree = self.get_tree(tree)?;
|
||||
let sql = format!("SELECT k, v FROM {} ORDER BY k DESC", tree);
|
||||
TxValueIterator::make(self, &sql, [])
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||||
make_tx_iterator(self, &sql, [])
|
||||
}
|
||||
|
||||
fn range<'r>(
|
||||
|
|
@ -396,7 +394,7 @@ impl<'a> ITx for SqliteTx<'a> {
|
|||
.map(|x| x as &dyn rusqlite::ToSql)
|
||||
.collect::<Vec<_>>();
|
||||
|
||||
TxValueIterator::make::<&[&dyn rusqlite::ToSql]>(self, &sql, params.as_ref())
|
||||
make_tx_iterator::<&[&dyn rusqlite::ToSql]>(self, &sql, params.as_ref())
|
||||
}
|
||||
fn range_rev<'r>(
|
||||
&self,
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||||
|
|
@ -414,77 +412,47 @@ impl<'a> ITx for SqliteTx<'a> {
|
|||
.map(|x| x as &dyn rusqlite::ToSql)
|
||||
.collect::<Vec<_>>();
|
||||
|
||||
TxValueIterator::make::<&[&dyn rusqlite::ToSql]>(self, &sql, params.as_ref())
|
||||
make_tx_iterator::<&[&dyn rusqlite::ToSql]>(self, &sql, params.as_ref())
|
||||
}
|
||||
}
|
||||
|
||||
// ---- iterators outside transactions ----
|
||||
// complicated, they must hold the Statement and Row objects
|
||||
// therefore quite some unsafe code (it is a self-referential struct)
|
||||
// so we need a self_referencing struct
|
||||
|
||||
struct DbValueIterator<'a> {
|
||||
// need to split in two because sequential mutable borrows are broken,
|
||||
// see https://github.com/someguynamedjosh/ouroboros/issues/100
|
||||
#[self_referencing]
|
||||
struct DbValueIterator1<'a> {
|
||||
db: MutexGuard<'a, SqliteDbInner>,
|
||||
stmt: Option<Statement<'a>>,
|
||||
iter: Option<Rows<'a>>,
|
||||
_pin: PhantomPinned,
|
||||
#[borrows(mut db)]
|
||||
#[covariant]
|
||||
stmt: Statement<'this>,
|
||||
}
|
||||
|
||||
impl<'a> DbValueIterator<'a> {
|
||||
fn make<P: rusqlite::Params>(
|
||||
#[self_referencing]
|
||||
struct DbValueIterator<'a> {
|
||||
aux: DbValueIterator1<'a>,
|
||||
#[borrows(mut aux)]
|
||||
#[covariant]
|
||||
iter: Rows<'this>,
|
||||
}
|
||||
|
||||
fn make_iterator<'a, P: rusqlite::Params>(
|
||||
db: MutexGuard<'a, SqliteDbInner>,
|
||||
sql: &str,
|
||||
args: P,
|
||||
) -> Result<ValueIter<'a>> {
|
||||
let res = DbValueIterator {
|
||||
db,
|
||||
stmt: None,
|
||||
iter: None,
|
||||
_pin: PhantomPinned,
|
||||
};
|
||||
let mut boxed = Box::pin(res);
|
||||
trace!("make iterator with sql: {}", sql);
|
||||
|
||||
// This unsafe allows us to bypass lifetime checks
|
||||
let db = unsafe { NonNull::from(&boxed.db).as_ref() };
|
||||
let stmt = db.db.prepare(sql)?;
|
||||
|
||||
let mut_ref = Pin::as_mut(&mut boxed);
|
||||
// This unsafe allows us to write in a field of the pinned struct
|
||||
unsafe {
|
||||
Pin::get_unchecked_mut(mut_ref).stmt = Some(stmt);
|
||||
}
|
||||
|
||||
// This unsafe allows us to bypass lifetime checks
|
||||
let stmt = unsafe { NonNull::from(&boxed.stmt).as_mut() };
|
||||
let iter = stmt.as_mut().unwrap().query(args)?;
|
||||
|
||||
let mut_ref = Pin::as_mut(&mut boxed);
|
||||
// This unsafe allows us to write in a field of the pinned struct
|
||||
unsafe {
|
||||
Pin::get_unchecked_mut(mut_ref).iter = Some(iter);
|
||||
}
|
||||
|
||||
Ok(Box::new(DbValueIteratorPin(boxed)))
|
||||
}
|
||||
) -> Result<ValueIter<'a>> {
|
||||
let aux = DbValueIterator1::try_new(db, |db| db.db.prepare(sql))?;
|
||||
let res = DbValueIterator::try_new(aux, |aux| aux.with_stmt_mut(|stmt| stmt.query(args)))?;
|
||||
Ok(Box::new(res))
|
||||
}
|
||||
|
||||
impl<'a> Drop for DbValueIterator<'a> {
|
||||
fn drop(&mut self) {
|
||||
trace!("drop iter");
|
||||
drop(self.iter.take());
|
||||
drop(self.stmt.take());
|
||||
}
|
||||
}
|
||||
|
||||
struct DbValueIteratorPin<'a>(Pin<Box<DbValueIterator<'a>>>);
|
||||
|
||||
impl<'a> Iterator for DbValueIteratorPin<'a> {
|
||||
impl<'a> Iterator for DbValueIterator<'a> {
|
||||
type Item = Result<(Value, Value)>;
|
||||
|
||||
fn next(&mut self) -> Option<Self::Item> {
|
||||
let mut_ref = Pin::as_mut(&mut self.0);
|
||||
// This unsafe allows us to mutably access the iterator field
|
||||
let next = unsafe { Pin::get_unchecked_mut(mut_ref).iter.as_mut()?.next() };
|
||||
let next = self.with_iter_mut(|iter| iter.next());
|
||||
iter_next_row(next)
|
||||
}
|
||||
}
|
||||
|
|
@ -493,57 +461,29 @@ impl<'a> Iterator for DbValueIteratorPin<'a> {
|
|||
// it's the same except we don't hold a mutex guard,
|
||||
// only a Statement and a Rows object
|
||||
|
||||
#[self_referencing]
|
||||
struct TxValueIterator<'a> {
|
||||
stmt: Statement<'a>,
|
||||
iter: Option<Rows<'a>>,
|
||||
_pin: PhantomPinned,
|
||||
#[borrows(mut stmt)]
|
||||
#[covariant]
|
||||
iter: Rows<'this>,
|
||||
}
|
||||
|
||||
impl<'a> TxValueIterator<'a> {
|
||||
fn make<P: rusqlite::Params>(
|
||||
fn make_tx_iterator<'a, P: rusqlite::Params>(
|
||||
tx: &'a SqliteTx<'a>,
|
||||
sql: &str,
|
||||
args: P,
|
||||
) -> TxOpResult<TxValueIter<'a>> {
|
||||
) -> TxOpResult<TxValueIter<'a>> {
|
||||
let stmt = tx.tx.prepare(sql)?;
|
||||
let res = TxValueIterator {
|
||||
stmt,
|
||||
iter: None,
|
||||
_pin: PhantomPinned,
|
||||
};
|
||||
let mut boxed = Box::pin(res);
|
||||
trace!("make iterator with sql: {}", sql);
|
||||
|
||||
// This unsafe allows us to bypass lifetime checks
|
||||
let stmt = unsafe { NonNull::from(&boxed.stmt).as_mut() };
|
||||
let iter = stmt.query(args)?;
|
||||
|
||||
let mut_ref = Pin::as_mut(&mut boxed);
|
||||
// This unsafe allows us to write in a field of the pinned struct
|
||||
unsafe {
|
||||
Pin::get_unchecked_mut(mut_ref).iter = Some(iter);
|
||||
}
|
||||
|
||||
Ok(Box::new(TxValueIteratorPin(boxed)))
|
||||
}
|
||||
let res = TxValueIterator::try_new(stmt, |stmt| stmt.query(args))?;
|
||||
Ok(Box::new(res))
|
||||
}
|
||||
|
||||
impl<'a> Drop for TxValueIterator<'a> {
|
||||
fn drop(&mut self) {
|
||||
trace!("drop iter");
|
||||
drop(self.iter.take());
|
||||
}
|
||||
}
|
||||
|
||||
struct TxValueIteratorPin<'a>(Pin<Box<TxValueIterator<'a>>>);
|
||||
|
||||
impl<'a> Iterator for TxValueIteratorPin<'a> {
|
||||
impl<'a> Iterator for TxValueIterator<'a> {
|
||||
type Item = TxOpResult<(Value, Value)>;
|
||||
|
||||
fn next(&mut self) -> Option<Self::Item> {
|
||||
let mut_ref = Pin::as_mut(&mut self.0);
|
||||
// This unsafe allows us to mutably access the iterator field
|
||||
let next = unsafe { Pin::get_unchecked_mut(mut_ref).iter.as_mut()?.next() };
|
||||
let next = self.with_iter_mut(|iter| iter.next());
|
||||
iter_next_row(next)
|
||||
}
|
||||
}
|
||||
|
|
|
|||
Loading…
Reference in a new issue