Erster Docker-Stand

_node_modules/postgres/cf/src/large.js

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+import Stream from 'node:stream'
+
+export default function largeObject(sql, oid, mode = 0x00020000 | 0x00040000) {
+  return new Promise(async(resolve, reject) => {
+    await sql.begin(async sql => {
+      let finish
+      !oid && ([{ oid }] = await sql`select lo_creat(-1) as oid`)
+      const [{ fd }] = await sql`select lo_open(${ oid }, ${ mode }) as fd`
+
+      const lo = {
+        writable,
+        readable,
+        close     : () => sql`select lo_close(${ fd })`.then(finish),
+        tell      : () => sql`select lo_tell64(${ fd })`,
+        read      : (x) => sql`select loread(${ fd }, ${ x }) as data`,
+        write     : (x) => sql`select lowrite(${ fd }, ${ x })`,
+        truncate  : (x) => sql`select lo_truncate64(${ fd }, ${ x })`,
+        seek      : (x, whence = 0) => sql`select lo_lseek64(${ fd }, ${ x }, ${ whence })`,
+        size      : () => sql`
+          select
+            lo_lseek64(${ fd }, location, 0) as position,
+            seek.size
+          from (
+            select
+              lo_lseek64($1, 0, 2) as size,
+              tell.location
+            from (select lo_tell64($1) as location) tell
+          ) seek
+        `
+      }
+
+      resolve(lo)
+
+      return new Promise(async r => finish = r)
+
+      async function readable({
+        highWaterMark = 2048 * 8,
+        start = 0,
+        end = Infinity
+      } = {}) {
+        let max = end - start
+        start && await lo.seek(start)
+        return new Stream.Readable({
+          highWaterMark,
+          async read(size) {
+            const l = size > max ? size - max : size
+            max -= size
+            const [{ data }] = await lo.read(l)
+            this.push(data)
+            if (data.length < size)
+              this.push(null)
+          }
+        })
+      }
+
+      async function writable({
+        highWaterMark = 2048 * 8,
+        start = 0
+      } = {}) {
+        start && await lo.seek(start)
+        return new Stream.Writable({
+          highWaterMark,
+          write(chunk, encoding, callback) {
+            lo.write(chunk).then(() => callback(), callback)
+          }
+        })
+      }
+    }).catch(reject)
+  })
+}