static program name (macro)

 * make program name into the macro PROG_NAME
 * add program name into all error messages

Signed-off-by: Daniel Santos <dacs.git@brilhante.top>

1 files changed, 6 insertions, 8 deletions

diff --git a/numericx.c b/numericx.c
index 2870b13..b8c0254 100644
--- a/numericx.c
+++ b/numericx.c
@@ -4,6 +4,8 @@
 #include <stdbool.h>
 #include <errno.h>
 
+#define PROG_NAME "numericx"
+
 #ifndef DEBUG
 #define DEBUG false
 #endif
@@ -39,8 +41,6 @@ typedef struct NumeralPtr
 	struct NumeralPtr *previous;
 } numeral_ptr;
 
-char* program_name = NULL;
-
 /*
  * Creates new digit for numeral_ptr
  * Return pointer to new numeral_ptr
@@ -52,7 +52,7 @@ new_digit(numeral_ptr* last_numeral, char const* to_first)
 	numeral_ptr* starting_point = malloc(sizeof(numeral_ptr));
 	if(starting_point == NULL)
 	{
-		fprintf(stderr, "error: %s: %s!", program_name, strerror(ENOMEM));
+		fprintf(stderr, "error: %s: %s!", PROG_NAME, strerror(ENOMEM));
 		return NULL;
 	}
 
@@ -210,12 +210,10 @@ free_numeral(numeral_ptr* numeral)
 int
 main(int argc, char* argv[])
 {
-	program_name = argv[0];
-
 	/* argument processing */
 	if( !(argc == 2) )
 	{
-		fprintf(stderr, "usage: %s <number>\n", program_name);
+		fprintf(stderr, "usage: %s <number>\n", PROG_NAME);
 		exit(EXIT_FAILURE);
 	}
 
@@ -234,7 +232,7 @@ main(int argc, char* argv[])
 	{
 		free(from);
 		free(to);
-		fprintf(stderr, "error: %s.\n", strerror(EDOM));
+		fprintf(stderr, "error: %s: %s.\n", PROG_NAME, strerror(EDOM));
 		exit(EDOM);
 	}
 
@@ -272,7 +270,7 @@ main(int argc, char* argv[])
 				free(to);
 				free_numeral(counting);
 				free_numeral(result);
-				fprintf(stderr, "error: unrepresentable void number\n");
+				fprintf(stderr, "error: %s: unrepresentable void number\n", PROG_NAME);
 				exit(EXIT_FAILURE);
 			}
 			decrement_number_string(number, from_first, from_last, from_first);