New flag -fdiagnostics-absolute-path to display full paths within err…

…or locations

This flag is useful for editors that cannot correctly locate files
with recursive build systems.

cobc/ChangeLog

@@ -1,4 +1,12 @@
 
+2023-10-02  Fabrice Le Fessant <fabrice.le_fessant@ocamlpro.com>
+
+	* error.c (print_error_prefix), flag.def: add new flag
+	  -fdiagnostics-absolute-path to print the full path of
+	  a file in case of error. This flag can be activated if
+	  your editor and build system do not correctly work
+	  together to locate files after errors within your project.
+
 2023-07-26  Simon Sobisch <simonsobisch@gnu.org>
 
 	* typeck.c (search_set_keys): improving SEARCH ALL syntax checks

cobc/error.c

@@ -28,6 +28,7 @@
 #include <ctype.h>
 #include <errno.h>
 #include <stdarg.h>
+#include <sys/stat.h>
 
 #include "cobc.h"
 #include "tree.h"
@@ -57,13 +58,36 @@ static void
 print_error_prefix (const char *file, int line, const char *prefix)
 {
 	if (file) {
+		char *absfile = NULL ;
+		if (cb_diagnostics_absolute_path
+		    && strcmp (file, COB_DASH) != 0
+		    && file[0] != '/'
+		    && file[0] != '\\'
+		    && ( file[0] != 0 && file[1] != ':' )
+			){
+			int filelen = strlen (file);
+			int dirlen = 256;
+			char *cwd ;
+			absfile = cobc_malloc( dirlen + 1 + filelen + 1 );
+			cwd = getcwd (absfile, dirlen);
+			if (cwd != NULL ){
+				struct stat st;
+				dirlen = strlen (cwd);
+				absfile[dirlen] = '/';
+				memcpy (absfile+dirlen+1, file, filelen+1);
+				if (!stat(absfile,&st)){
+					file = absfile;
+				}
+			}
+		}
 		if (line <= 0) {
 			fprintf (stderr, "%s: ", file);
 		} else if (cb_msg_style == CB_MSG_STYLE_MSC) {
 			fprintf (stderr, "%s(%d): ", file, line);
 		} else {
 			fprintf (stderr, "%s:%d: ", file, line);
 		}
+		if (absfile) cobc_free (absfile);
 	}
 	if (prefix) {
 		fprintf (stderr, "%s", prefix);

cobc/flag.def

@@ -254,3 +254,6 @@ CB_FLAG_ON (cb_diagnostics_show_caret, 1, "diagnostics-show-caret",
 
 CB_FLAG_ON (cb_diagnostics_show_line_numbers, 1, "diagnostics-show-line-numbers",
 	_("  -fno-diagnostics-show-line-numbers\tsuppress display of line numbers in diagnostics"))
+
+CB_FLAG (cb_diagnostics_absolute_path, 1, "diagnostics-absolute-path",
+	_("  -fdiagnostics-absolute-path\tdisplay paths with absolute paths"))