CLI: add --version long argument to return PROJ version

Author: lbartoletti

src/apps/proj.cpp

@@ -496,6 +496,11 @@ int main(int argc, char **argv) {
                 case 's': /* reverse output */
                     reverseout = 1;
                     continue;
+                case '-': /* long option */
+                    if (std::strcmp(*argv, "--version") == 0) {
+                        (void)printf("%s\n", pj_get_version());
+                        exit(0);
+                    }
                 default:
                     emess(1, "invalid option: -%c", *arg);
                     break;

src/proj_internal.h

@@ -1004,6 +1004,7 @@ int pj_has_inverse(PJ *);
 
 char *pj_strdup(const char *str);
 const char PROJ_DLL *pj_get_release(void);
+const char PROJ_DLL *pj_get_version(void);
 void pj_acquire_lock(void);
 void pj_release_lock(void);
 

src/release.cpp

@@ -6,6 +6,11 @@
 #define STR_HELPER(x) #x
 #define STR(x) STR_HELPER(x)
 
+char const pj_version[] = STR(PROJ_VERSION_MAJOR) "." STR(
+    PROJ_VERSION_MINOR) "." STR(PROJ_VERSION_PATCH);
+
+const char *pj_get_version() { return pj_version; }
+
 char const pj_release[] = "Rel. " STR(PROJ_VERSION_MAJOR) "." STR(
     PROJ_VERSION_MINOR) "." STR(PROJ_VERSION_PATCH) ", "
                                                     "September 1st, 2023";