r.mask.status: Check mask status through module

Instead of using low-level test of file existence with hardcoded raster path and name, use a module to retrieve status of the raster mask.

The new module r.mask.status reports presence or absence of the 2D raster mask and provides additional details about the mask.

The PR requires additional changes in the library which are not yet included.

include/grass/defs/raster.h

@@ -401,6 +401,7 @@ int Rast_option_to_interp_type(const struct Option *);
 
 /* mask_info.c */
 char *Rast_mask_info(void);
+bool Rast_mask_status(char *, char *, bool *);
 int Rast__mask_info(char *, char *);
 
 /* maskfd.c */

lib/init/grass.py

@@ -1998,8 +1998,8 @@ def sh_like_startup(location, location_name, grass_env_file, sh):
             )
         )
 
+    mask2d_test = 'r.mask.status -t'
     # TODO: have a function and/or module to test this
-    mask2d_test = 'test -f "$MAPSET_PATH/cell/MASK"'
     mask3d_test = 'test -d "$MAPSET_PATH/grid3/RASTER3D_MASK"'
 
     specific_addition = ""

raster/r.mask.status/Makefile

@@ -0,0 +1,10 @@
+MODULE_TOPDIR = ../..
+
+PGM = r.mask.status
+
+LIBES = $(MANAGELIB) $(RASTERLIB) $(GISLIB)
+DEPENDENCIES = $(MANAGEDEP) $(RASTERDEP) $(GISDEP)
+
+include $(MODULE_TOPDIR)/include/Make/Module.make
+
+default: cmd

raster/r.mask.status/main.c

@@ -0,0 +1,168 @@
+/****************************************************************************
+ *
+ * MODULE:       r.mask.status
+ * AUTHORS:      Vaclav Petras
+ * PURPOSE:      Report status of raster mask
+ * COPYRIGHT:    (C) 2022 by Vaclav Petras and the GRASS Development Team
+ *
+ *               This program is free software under the GNU General Public
+ *               License (>=v2). Read the file COPYING that comes with GRASS
+ *               for details.
+ *
+ *****************************************************************************/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <grass/gis.h>
+#include <grass/raster.h>
+#include <grass/glocale.h>
+
+struct Parameters
+{
+    struct Option *format;
+    struct Flag *like_test;
+};
+
+void parse_parameters(struct Parameters *params, int argc, char **argv)
+{
+    struct GModule *module;
+
+    module = G_define_module();
+    G_add_keyword(_("raster"));
+    G_add_keyword(_("reclassification"));
+    module->label = _("Reclassify raster map based on category values.");
+    module->description =
+        _("Creates a new raster map whose category values are based "
+          "upon a reclassification of the categories in an existing "
+          "raster map.");
+
+    params->format = G_define_option();
+    params->format->key = "format";
+    params->format->type = TYPE_STRING;
+    params->format->required = NO;
+    params->format->answer = "yaml";
+    params->format->options = "yaml,json,bash";
+    params->format->description = _("Format for reporting");
+
+    params->like_test = G_define_flag();
+    params->like_test->key = 't';
+    params->like_test->lable =
+        _("Return code 0 when mask present, 1 otherwise");
+    params->like_test->description =
+        _("Behave like the test utility, 0 for true, 1 for false, no output");
+    //flags.like_test->guisection = _("");
+    // suppress_required
+
+    if (G_parser(argc, argv))
+        exit(EXIT_FAILURE);
+}
+
+char *min_json_escape(const char *str)
+{
+    char *tmp1 = G_str_replace(str, "\\", "\\\\");
+    char *tmp2 = G_str_replace(tmp1, "\"", "\\\"");
+
+    G_free(tmp1);
+    return tmp2;
+}
+
+void json_print_name_mapset(const char *name, const char *mapset)
+{
+    // Being paranoid about what is in the name.
+    char *escaped_name = min_json_escape(name);
+    char *escaped_mapset = min_json_escape(mapset);
+
+    printf("\"%s@%s\"", name, mapset);
+    G_free(escaped_name);
+    G_free(escaped_mapset);
+}
+
+int report_status(struct Parameters *params)
+{
+
+    char name[GNAME_MAX];
+    char mapset[GMAPSET_MAX];
+
+    bool is_mask_reclass;
+    bool present =
+        Rast_mask_status(name, mapset, reclass_name, reclass_mapset,
+                         &is_mask_reclass);
+    bool present = Rast_mask_present(name, mapset);
+
+    //printf("%s", Rast_mask_info());
+
+    if (params->like_test->answer) {
+        if (present)
+            return 0;
+        else
+            return 1;
+    }
+    else if (strcmp(params->format->answer, "json") == 0) {
+        printf("{\"present\":");
+        if (present)
+            printf("true");
+        else
+            printf("false");
+        printf(",\n\"full_name\":");
+        if (present)
+            json_print_name_mapset("MASK", G_mapset()); // Too much mask details here, move this to the library.
+        else
+            printf("null");
+        printf(",\n\"is_reclass_of\": ");
+        if (is_mask_reclass)
+            json_print_name_mapset(name, mapset);
+        else
+            printf("null");
+        printf("}\n");
+    }
+    else if (strcmp(params->format->answer, "bash") == 0) {
+        printf("present=");
+        if (present)
+            printf("1");        // Good choice here or not?
+        else
+            printf("0");
+        printf("\nfull_name=");
+        if (present) {
+            json_print_name_mapset(name, mapset);
+        }
+        printf("\n");
+    }
+    else {
+        printf("present: ");
+        if (present)
+            printf("true");
+        else
+            printf("false");
+        printf("\nfull_name: ");
+        if (present)
+            printf("|-\n  MASK@%s", G_mapset());        // MASK or MASK@current_mapset
+        else
+            printf("null");
+        printf("\nis_reclass_of: ");
+        // Using block scalar with |- to avoid need for escaping.
+        if (is_mask_reclass)
+            printf("|-\n  %s@%s", name, mapset);
+        else
+            printf("null");
+        // true if MASK in current mapset and is reclass, false otherwise,
+        // then also outputting mask cats is needed to inform user about the portion of the map
+        // printf("\nmask_reclass: ");
+        // if (is_mask_reclass)
+        //     printf("true");
+        // else
+        //     printf("false");
+        printf("\n");
+    }
+    return EXIT_SUCCESS;
+}
+
+int main(int argc, char **argv)
+{
+    struct Parameters params;
+
+    G_gisinit(argv[0]);
+    parse_parameters(&params, argc, argv);
+    return report_status(&params);
+}

raster/r.mask.status/r.mask.status.html

@@ -0,0 +1,35 @@
+<h2>DESCRIPTION</h2>
+
+<em>r.mask.status</em> reports presence or absence of a raster mask.
+
+<h2>NOTES</h2>
+
+<h2>EXAMPLES</h2>
+
+<h3>Generate JSON output</h3>
+
+<div class="code"><pre>
+r.mask.status format=json
+</pre></div>
+
+<h3>Use as the test utility</h3>
+
+The POSIX <em>test</em> utility uses return code 0 to indicate true
+and 1 to indicate false, so testing existence of a file with <code>test -f</code>
+gives return code 0 when the file exists. <em>r.mask.status</em> can be used
+in the same with the the <b>-t</b> flag:
+
+<div class="code"><pre>
+r.mask.status -t
+</pre></div>
+
+<h2>SEE ALSO</h2>
+
+<em>
+<a href="r.mask.html">r.mask</a>,
+<a href="g.region.html">g.region</a>
+</em>
+
+<h2>AUTHORS</h2>
+
+Vaclav Petras, NC State University, Center for Geospatial Analytics