From 61e6e3970f2fe1a63ad590a2f30383dff835f211 Mon Sep 17 00:00:00 2001
From: Dennis Heimbigner <dennis.heimbigner@gmail.com>
Date: Mon, 10 Feb 2025 18:52:09 -0700
Subject: [PATCH] Provide an auxilliary function that allows users to parse the
_NCProperties attribute.
re: Discussion https://github.com/Unidata/netcdf-c/discussions/3085
This discussion raised the issue of the best way to distinguish
a netcdfd-c created file and an HDF5 created file. The
recommended way is to use the _NCProperties attribute. In order
for users to process this attribute, I have added a parser for
the attribute to the netcdf_aux.h file.
---
RELEASE_NOTES.md | 4 ++
include/netcdf_aux.h | 7 ++
libdispatch/daux.c | 127 ++++++++++++++++++++++++++++++++++++
ncdap_test/Makefile.am | 1 -
unit_test/Makefile.am | 6 ++
unit_test/ref_provparse.txt | 4 ++
unit_test/run_auxmisc.sh | 31 +++++++++
unit_test/test_auxmisc.c | 111 +++++++++++++++++++++++++++++++
8 files changed, 290 insertions(+), 1 deletion(-)
create mode 100644 unit_test/ref_provparse.txt
create mode 100755 unit_test/run_auxmisc.sh
create mode 100644 unit_test/test_auxmisc.c
diff --git a/RELEASE_NOTES.md b/RELEASE_NOTES.md
index a1a0d8766..2b6fa29aa 100644
--- a/RELEASE_NOTES.md
+++ b/RELEASE_NOTES.md
@@ -5,6 +5,10 @@ Release Notes {#RELEASE_NOTES}
This file contains a high-level description of this package's evolution. Releases are in reverse chronological order (most recent first). Note that, as of netcdf 4.2, the `netcdf-c++` and `netcdf-fortran` libraries have been separated into their own libraries.
+## 4.9.4 - TBD
+
+* Provide an auxilliary function that allows users to parse the _NCProperties attribute. See [Github #????](https://github.com/Unidata/netcdf-c/pull/????) for more information.
+
## 4.9.3 - February 7, 2025
## Known Issues
diff --git a/include/netcdf_aux.h b/include/netcdf_aux.h
index 64bf603bf..1985b00f1 100644
--- a/include/netcdf_aux.h
+++ b/include/netcdf_aux.h
@@ -245,6 +245,13 @@ EXTERNL int ncaux_plugin_path_stringget(int pathlen, char* path);
*/
EXTERNL int ncaux_plugin_path_stringset(int pathlen, const char* path);
+/* Provide a parser for _NCProperties attribute.
+ * @param ncprop the contents of the _NCProperties attribute.
+ * @param pairsp allocate and return a pointer to a NULL terminated vector of (key,value) pairs.
+ * @return NC_NOERR | NC_EXXX
+ */
+EXTERNL int ncaux_parse_provenance(const char* ncprop, char*** pairsp);
+
#if defined(__cplusplus)
}
#endif
diff --git a/libdispatch/daux.c b/libdispatch/daux.c
index 71e2a7c52..da2917b0f 100644
--- a/libdispatch/daux.c
+++ b/libdispatch/daux.c
@@ -31,6 +31,7 @@ See COPYRIGHT for license information.
#include "ncrc.h"
#include "netcdf_filter.h"
#include "ncpathmgr.h"
+#include "nclist.h"
struct NCAUX_FIELD {
char* name;
@@ -1274,3 +1275,129 @@ done:
if(npl.dirs != NULL) {(void)ncaux_plugin_path_clear(&npl);}
return stat;
}
+
+/**************************************************/
+
+/* De-escape a string */
+static char*
+deescape(const char* s)
+{
+ char* des = strdup(s);
+ char* p = NULL;
+ char* q = NULL;
+ if(s == NULL) return NULL;
+ for(p=des,q=des;*p;) {
+ switch (*p) {
+ case '\\':
+ p++;
+ if(*p == '\0') {*q++ = '\\';} break; /* edge case */
+ /* fall thru */
+ default:
+ *q++ = *p++;
+ break;
+ }
+ }
+ *q = '\0';
+ return des;
+}
+
+/**
+ * @internal
+ *
+ * Construct the parsed provenance information
+ * Provide a parser for _NCProperties attribute.
+ * @param ncprop the contents of the _NCProperties attribute.
+ * @param pairsp allocate and return a pointer to a NULL terminated vector of (key,value) pairs.
+ * @return NC_NOERR | NC_EXXX
+ */
+int
+ncaux_parse_provenance(const char* ncprop0, char*** pairsp)
+{
+ int stat = NC_NOERR;
+ NClist* pairs = NULL;
+ char* ncprop = NULL;
+ size_t ncproplen = 0;
+ char* thispair = NULL;
+ char* p = NULL;
+ int i,count = 0;
+ int endinner;
+
+ if(pairsp == NULL) goto done;
+ *pairsp = NULL;
+ ncproplen = nulllen(ncprop0);
+
+ if(ncproplen == 0) goto done;
+
+ ncprop = (char*)malloc(ncproplen+1+1); /* double nul term */
+ strcpy(ncprop,ncprop0); /* Make modifiable copy */
+ ncprop[ncproplen] = '\0'; /* double nul term */
+ ncprop[ncproplen+1] = '\0'; /* double nul term */
+ pairs = nclistnew();
+
+ /* delimit the key,value pairs */
+ thispair = ncprop;
+ count = 0;
+ p = thispair;
+ endinner = 0;
+ do {
+ switch (*p) {
+ case '\0':
+ if(strlen(thispair)==0) {stat = NC_EINVAL; goto done;} /* Has to be a non-null key */
+ endinner = 1; /* terminate loop */
+ break;
+ case ',': case '|': /* '|' is version one pair separator */
+ *p++ = '\0'; /* terminate this pair */
+ if(strlen(thispair)==0) {stat = NC_EINVAL; goto done;} /* Has to be a non-null key */
+ thispair = p;
+ count++;
+ break;
+ case '\\':
+ p++; /* skip the escape and escaped char */
+ /* fall thru */
+ default:
+ p++;
+ break;
+ }
+ } while(!endinner);
+ count++;
+ /* Split and store the pairs */
+ thispair = ncprop;
+ for(i=0;i<count;i++) {
+ char* key = thispair;
+ char* value = NULL;
+ char* nextpair = (thispair + strlen(thispair) + 1);
+ /* Find the '=' separator for each pair */
+ p = thispair;
+ endinner = 0;
+ do {
+ switch (*p) {
+ case '\0': /* Key has no value */
+ value = p;
+ endinner = 1; /* => leave loop */
+ break;
+ case '=':
+ *p++ = '\0'; /* split this pair */
+ value = p;
+ endinner = 1;
+ break;
+ case '\\':
+ p++; /* skip the escape + escaped char */
+ /* fall thru */
+ default:
+ p++;
+ break;
+ }
+ } while(!endinner);
+ /* setup next iteration */
+ nclistpush(pairs,deescape(key));
+ nclistpush(pairs,deescape(value));
+ thispair = nextpair;
+ }
+ /* terminate the list with (NULL,NULL) key value pair*/
+ nclistpush(pairs,NULL); nclistpush(pairs,NULL);
+ *pairsp = (char**)nclistextract(pairs);
+done:
+ nullfree(ncprop);
+ nclistfreeall(pairs);
+ return stat;
+}
diff --git a/ncdap_test/Makefile.am b/ncdap_test/Makefile.am
index e7d8ff834..41c16b666 100644
--- a/ncdap_test/Makefile.am
+++ b/ncdap_test/Makefile.am
@@ -66,7 +66,6 @@ endif
if NETCDF_ENABLE_DAP_LONG_TESTS
test_manyurls_SOURCES = test_manyurls.c manyurls.h
-check_PROGRAMS += test_manyurls
test_manyurls.log: tst_longremote3.log
TESTS += test_manyurls
endif
diff --git a/unit_test/Makefile.am b/unit_test/Makefile.am
index 90eef59c5..e1ae642f1 100644
--- a/unit_test/Makefile.am
+++ b/unit_test/Makefile.am
@@ -60,10 +60,16 @@ check_PROGRAMS += aws_config
TESTS += run_aws_config.sh
endif
+# Test misc. netcdf_aux functions
+check_PROGRAMS += test_auxmisc
+TESTS += run_auxmisc.sh
+
EXTRA_DIST = CMakeLists.txt run_s3sdk.sh run_reclaim_tests.sh run_aws_config.sh run_pluginpaths.sh run_dfaltpluginpath.sh
+EXTRA_DIST += run_auxmisc.sh
EXTRA_DIST += nctest_netcdf4_classic.nc reclaim_tests.cdl
EXTRA_DIST += ref_get.txt ref_set.txt
EXTRA_DIST += ref_xget.txt ref_xset.txt
+EXTRA_DIST += ref_provparse.txt
CLEANFILES = reclaim_tests*.txt reclaim_tests.nc tmp_*.txt
diff --git a/unit_test/ref_provparse.txt b/unit_test/ref_provparse.txt
new file mode 100644
index 000000000..136a0655a
--- /dev/null
+++ b/unit_test/ref_provparse.txt
@@ -0,0 +1,4 @@
+abc=2\|z\=17,yyy=|zzz -> (/abc/,/2|z=17/) (/yyy/,//) (/zzz/,//)
+version=2,netcdf=4.7.4-development,hdf5=1.10.4 -> (/version/,/2/) (/netcdf/,/4.7.4-development/) (/hdf5/,/1.10.4/)
+version=2,netcdf=4.6.2-development,hdf5=1.10.1 -> (/version/,/2/) (/netcdf/,/4.6.2-development/) (/hdf5/,/1.10.1/)
+version=1|netcdf=4.6.2-development|hdf5=1.8.1 -> (/version/,/1/) (/netcdf/,/4.6.2-development/) (/hdf5/,/1.8.1/)
diff --git a/unit_test/run_auxmisc.sh b/unit_test/run_auxmisc.sh
new file mode 100755
index 000000000..70c6e5552
--- /dev/null
+++ b/unit_test/run_auxmisc.sh
@@ -0,0 +1,31 @@
+#!/bin/sh
+
+if test "x$srcdir" = x ; then srcdir=`pwd`; fi
+. ../test_common.sh
+
+set -e
+
+# List of provenance strings to parse
+# Start with some edge cases
+TESTS=
+TESTS="$TESTS abc=2\|z\=17,yyy=|zzz"
+TESTS="$TESTS version=2,netcdf=4.7.4-development,hdf5=1.10.4"
+TESTS="$TESTS version=2,netcdf=4.6.2-development,hdf5=1.10.1"
+TESTS="$TESTS version=1|netcdf=4.6.2-development|hdf5=1.8.1"
+
+# Test provenance parsing
+testprov() {
+rm -f tmp_provparse.txt
+for t in $TESTS ; do
+${execdir}/test_auxmisc -P ${t} >> tmp_provparse.txt
+done
+echo "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"
+cat ${srcdir}/ref_provparse.txt
+echo "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"
+cat tmp_provparse.txt
+echo "@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@@"
+# Verify
+#diff ref_provparse.txt tmp_provparse.txt
+}
+
+testprov
diff --git a/unit_test/test_auxmisc.c b/unit_test/test_auxmisc.c
new file mode 100644
index 000000000..6040230fb
--- /dev/null
+++ b/unit_test/test_auxmisc.c
@@ -0,0 +1,111 @@
+/*********************************************************************
+ * Copyright 2018, UCAR/Unidata
+ * See netcdf/COPYRIGHT file for copying and redistribution conditions.
+ *********************************************************************/
+
+/**
+Test miscellaneous netcdf_aux functions.
+*/
+
+#include "config.h"
+#include <stdlib.h>
+#include <stdio.h>
+#include <string.h>
+#include <assert.h>
+#include "netcdf.h"
+#include "netcdf_aux.h"
+
+#define NCCATCH
+#include "nclog.h"
+
+#ifdef HAVE_GETOPT_H
+#include <getopt.h>
+#endif
+
+#if defined(_WIN32) && !defined(__MINGW32__)
+#include "XGetopt.h"
+#endif
+
+#define DEBUG
+
+typedef enum CMD {cmd_none=0, cmd_prov=1} CMD;
+
+struct Options {
+ int debug;
+ CMD cmd;
+ int argc;
+ char** argv;
+} options;
+
+#define CHECK(code) do {stat = check(code,__func__,__LINE__); if(stat) {goto done;}} while(0)
+
+static int
+check(int code, const char* fcn, int line)
+{
+ if(code == NC_NOERR) return code;
+ fprintf(stderr,"***fail: (%d) %s @ %s:%d\n",code,nc_strerror(code),fcn,line);
+#ifdef debug
+ abort();
+#endif
+ exit(1);
+}
+
+static void
+testprov(void)
+{
+ int stat = NC_NOERR;
+ int i;
+ char** list = NULL;
+ assert(options.argc > 0);
+ for(i=0;i<options.argc;i++) {
+ char** p;
+ CHECK(ncaux_parse_provenance(options.argv[i],&list));
+ /* Print and reclaim */
+ printf("%s -> ",options.argv[i]);
+ for(p=list;*p;p+=2) {
+ printf(" (/%s/,/%s/)",p[0],p[1]);
+ free(p[0]);
+ if(p[1]) free(p[1]);
+ }
+ printf("\n");
+ free(list); list = NULL;
+ }
+done:
+ return;
+}
+
+int
+main(int argc, char** argv)
+{
+ int stat = NC_NOERR;
+ int c;
+ /* Init options */
+ memset((void*)&options,0,sizeof(options));
+
+ while ((c = getopt(argc, argv, "dP")) != EOF) {
+ switch(c) {
+ case 'd':
+ options.debug = 1;
+ break;
+ case 'P':
+ options.cmd = cmd_prov;
+ break;
+ case '?':
+ fprintf(stderr,"unknown option\n");
+ stat = NC_EINVAL;
+ goto done;
+ }
+ }
+
+ /* Setup args */
+ argc -= optind;
+ argv += optind;
+ options.argc = argc;
+ options.argv = argv;
+ switch (options.cmd) {
+ case cmd_prov: testprov(); break;
+ default: fprintf(stderr,"Unknown cmd\n"); abort(); break;
+ }
+done:
+ return (stat?1:0);
+}