funcs: Make intdiv truncate to int

wader · Sep 12, 2021 · 962d84d · 962d84d
1 parent 48517c7
commit 962d84d
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Showing 3 changed files with 46 additions and 4 deletions.
diff --git a/format/mp4/mp4.go b/format/mp4/mp4.go
@@ -240,7 +240,14 @@ func mp4Decode(d *decode.D, in interface{}) interface{} {
 							sampleSize := t.stsz[sampleNr]
 							decodeSampleRange(d, t, trackSdDataFormat, "sample", int64(sampleOffset)*8, int64(sampleSize)*8, t.decodeOpts...)
 
-							// log.Printf("%s %d/%d %d/%d sample=%d/%d chunk=%d size=%d %d-%d\n", t.dataFormat, stscIndex, len(t.stsc), i, stscEntry.samplesPerChunk, sampleNr, len(t.stsz), chunkNr, sampleSize, sampleOffset, sampleOffset+uint64(sampleSize))
+							// log.Printf("%s %d/%d %d/%d sample=%d/%d chunk=%d size=%d %d-%d\n",
+							// 	trackSdDataFormat, stscIndex, len(t.stsc),
+							// 	i, stscEntry.samplesPerChunk,
+							// 	sampleNr, len(t.stsz),
+							// 	chunkNr,
+							// 	sampleSize,
+							// 	sampleOffset,
+							// 	sampleOffset+uint64(sampleSize))
 
 							sampleOffset += uint64(sampleSize)
 							sampleNr++

diff --git a/pkg/interp/funcs.jq b/pkg/interp/funcs.jq
@@ -15,9 +15,17 @@ def decode($name; $opts): _decode($name; $opts);
 def decode($name): _decode($name; {});
 def decode: _decode("probe"; {});
 
+
+# TODO: figure out a saner way to force int
+def _to_int: (. % (. + 1));
+
 # integer division
 # inspried by https://github.com/itchyny/gojq/issues/63#issuecomment-765066351
-def intdiv($a; $b): ($a - ($a % $b)) / $b;
+def intdiv($a; $b):
+  ( ($a | _to_int) as $a
+  | ($b | _to_int) as $b
+  | ($a - ($a % $b)) / $b
+  );
 
 # valid jq identifier, start with alpha or underscore then zero or more alpha, num or underscore
 def _is_ident: type == "string" and test("^[a-zA-Z_][a-zA-Z_0-9]*$");
@@ -204,8 +212,6 @@ def table(colmap; render):
 
 # convert number to array of bytes
 def number_to_bytes($bits):
-  # TODO: figure out a saner way to force int
-  def _to_int: (. % (. + 1));
   def _number_to_bytes($d):
     if . > 0 then
       . % $d, (intdiv(.; $d) | _number_to_bytes($d))

diff --git a/pkg/interp/funcs_test.jq b/pkg/interp/funcs_test.jq
@@ -45,4 +45,33 @@ include "funcs";
     ["1234", 2, ["12","34"]],
     ["1234", 3, ["123","4"]]
   ][] | . as $t | assert("\($t[0]) | chunk(\($t[1]))"; $t[2]; $t[0] | chunk($t[1])))
+,
+  ([
+    # 0xfffffffffffffffffffffffffffffffffffffffffffff
+    [1532495540865888858358347027150309183618739122183602175, 8, [
+      15,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255,
+      255
+    ]]
+  ][] | . as $t | assert("\($t[0]) | number_to_bytes(\($t[1]))"; $t[2]; $t[0] | number_to_bytes($t[1])))
 )