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-rw-r--r--vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_other.go9
-rw-r--r--vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_slice.go24
-rw-r--r--vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_unix.go67
-rw-r--r--vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_windows.go76
4 files changed, 176 insertions, 0 deletions
diff --git a/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_other.go b/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_other.go
new file mode 100644
index 000000000..ded8da108
--- /dev/null
+++ b/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_other.go
@@ -0,0 +1,9 @@
+//go:build !(unix || windows) || sqlite3_nosys
+
+package alloc
+
+import "github.com/tetratelabs/wazero/experimental"
+
+func Virtual(cap, max uint64) experimental.LinearMemory {
+ return Slice(cap, max)
+}
diff --git a/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_slice.go b/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_slice.go
new file mode 100644
index 000000000..5072ca9c1
--- /dev/null
+++ b/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_slice.go
@@ -0,0 +1,24 @@
+//go:build !(darwin || linux) || !(amd64 || arm64 || riscv64) || sqlite3_noshm || sqlite3_nosys
+
+package alloc
+
+import "github.com/tetratelabs/wazero/experimental"
+
+func Slice(cap, _ uint64) experimental.LinearMemory {
+ return &sliceMemory{make([]byte, 0, cap)}
+}
+
+type sliceMemory struct {
+ buf []byte
+}
+
+func (b *sliceMemory) Free() {}
+
+func (b *sliceMemory) Reallocate(size uint64) []byte {
+ if cap := uint64(cap(b.buf)); size > cap {
+ b.buf = append(b.buf[:cap], make([]byte, size-cap)...)
+ } else {
+ b.buf = b.buf[:size]
+ }
+ return b.buf
+}
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
+}
diff --git a/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_windows.go b/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_windows.go
new file mode 100644
index 000000000..27d875f2e
--- /dev/null
+++ b/vendor/github.com/ncruces/go-sqlite3/internal/alloc/alloc_windows.go
@@ -0,0 +1,76 @@
+//go:build !sqlite3_nosys
+
+package alloc
+
+import (
+ "math"
+ "reflect"
+ "unsafe"
+
+ "github.com/tetratelabs/wazero/experimental"
+ "golang.org/x/sys/windows"
+)
+
+func Virtual(_, max uint64) experimental.LinearMemory {
+ // Round up to the page size.
+ rnd := uint64(windows.Getpagesize() - 1)
+ max = (max + rnd) &^ rnd
+
+ if max > math.MaxInt {
+ // This ensures uintptr(max) overflows to a large value,
+ // and windows.VirtualAlloc returns an error.
+ max = math.MaxUint64
+ }
+
+ // Reserve max bytes of address space, to ensure we won't need to move it.
+ // This does not commit memory.
+ r, err := windows.VirtualAlloc(0, uintptr(max), windows.MEM_RESERVE, windows.PAGE_READWRITE)
+ if err != nil {
+ panic(err)
+ }
+
+ mem := virtualMemory{addr: r}
+ // SliceHeader, although deprecated, avoids a go vet warning.
+ sh := (*reflect.SliceHeader)(unsafe.Pointer(&mem.buf))
+ sh.Cap = int(max)
+ sh.Data = r
+ return &mem
+}
+
+// The slice covers the entire mmapped memory:
+// - len(buf) is the already committed memory,
+// - cap(buf) is the reserved address space.
+type virtualMemory struct {
+ buf []byte
+ addr uintptr
+}
+
+func (m *virtualMemory) 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(windows.Getpagesize() - 1)
+ new := (size + rnd) &^ rnd
+
+ // Commit additional memory up to new bytes.
+ _, err := windows.VirtualAlloc(m.addr, uintptr(new), windows.MEM_COMMIT, windows.PAGE_READWRITE)
+ 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 *virtualMemory) Free() {
+ err := windows.VirtualFree(m.addr, 0, windows.MEM_RELEASE)
+ if err != nil {
+ panic(err)
+ }
+ m.addr = 0
+}