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authorLibravatar Daenney <daenney@users.noreply.github.com>2024-06-07 15:06:43 +0200
committerLibravatar GitHub <noreply@github.com>2024-06-07 15:06:43 +0200
commitcc4f773b0e0f45cdb28727853b9d253234a93b56 (patch)
tree455224a7cb489909906eda5778d0e700867358d4 /vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_unix.go
parent[feature] Implement filters_changed stream event (#2972) (diff)
downloadgotosocial-cc4f773b0e0f45cdb28727853b9d253234a93b56.tar.xz
[chore] Update WASM go-sqlite3 to v0.16.1 (#2976)
This includes support for journal mode set to WAL on the BSDs. Relates to: #1753, #2962
Diffstat (limited to 'vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_unix.go')
-rw-r--r--vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_unix.go67
1 files changed, 67 insertions, 0 deletions
diff --git a/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_unix.go b/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_unix.go
new file mode 100644
index 000000000..39a3a38cc
--- /dev/null
+++ b/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_unix.go
@@ -0,0 +1,67 @@
+//go:build unix && !sqlite3_nosys
+
+package alloc
+
+import (
+ "math"
+
+ "github.com/tetratelabs/wazero/experimental"
+ "golang.org/x/sys/unix"
+)
+
+func Virtual(_, max uint64) experimental.LinearMemory {
+ // Round up to the page size.
+ rnd := uint64(unix.Getpagesize() - 1)
+ max = (max + rnd) &^ rnd
+
+ if max > math.MaxInt {
+ // This ensures int(max) overflows to a negative value,
+ // and unix.Mmap returns EINVAL.
+ max = math.MaxUint64
+ }
+
+ // Reserve max bytes of address space, to ensure we won't need to move it.
+ // A protected, private, anonymous mapping should not commit memory.
+ b, err := unix.Mmap(-1, 0, int(max), unix.PROT_NONE, unix.MAP_PRIVATE|unix.MAP_ANON)
+ if err != nil {
+ panic(err)
+ }
+ return &mmappedMemory{buf: b[:0]}
+}
+
+// The slice covers the entire mmapped memory:
+// - len(buf) is the already committed memory,
+// - cap(buf) is the reserved address space.
+type mmappedMemory struct {
+ buf []byte
+}
+
+func (m *mmappedMemory) Reallocate(size uint64) []byte {
+ com := uint64(len(m.buf))
+ res := uint64(cap(m.buf))
+ if com < size && size < res {
+ // Round up to the page size.
+ rnd := uint64(unix.Getpagesize() - 1)
+ new := (size + rnd) &^ rnd
+
+ // Commit additional memory up to new bytes.
+ err := unix.Mprotect(m.buf[com:new], unix.PROT_READ|unix.PROT_WRITE)
+ if err != nil {
+ panic(err)
+ }
+
+ // Update committed memory.
+ m.buf = m.buf[:new]
+ }
+ // Limit returned capacity because bytes beyond
+ // len(m.buf) have not yet been committed.
+ return m.buf[:size:len(m.buf)]
+}
+
+func (m *mmappedMemory) Free() {
+ err := unix.Munmap(m.buf[:cap(m.buf)])
+ if err != nil {
+ panic(err)
+ }
+ m.buf = nil
+}