1 files changed, 29 insertions, 0 deletions
diff --git a/lib/bib-select.awk b/lib/bib-select.awk
new file mode 100644
index 0000000..1900390
--- /dev/null
+++ b/lib/bib-select.awk
@@ -0,0 +1,29 @@
+# bib-select.awk - emit entries selected by key, canonically
+#
+# Requires bib-parse.awk and bib-canon.awk. Variables (set with -v):
+#   keys   - comma-separated list of entry keys
+#   invert - 0: emit entries whose key is in the list
+#            1: emit entries whose key is NOT in the list
+#
+# With keys="" and invert=1 this acts as a canonicalizing filter for
+# everything. @string and @preamble blocks always pass through.
+
+BEGIN {
+  bib_sel_n = split(keys, bib_sel_k, ",")
+  for (bib_sel_i = 1; bib_sel_i <= bib_sel_n; bib_sel_i++)
+    BIB_SEL[bib_sel_k[bib_sel_i]] = 1
+}
+
+function bib_pass(raw) {
+  if (bib_out_n++)
+    print ""
+  print raw
+}
+
+function bib_entry(type, key) {
+  if ((key in BIB_SEL) != invert + 0) {
+    if (bib_out_n++)
+      print ""
+    bib_emit(type, key)
+  }
+}