Implement src/error.c

Implement src/error.c to provide the patty_error type, to allow easy
error string formatting, error state checking, and error clearing

include/patty/error.h

@@ -0,0 +1,24 @@
+#ifndef _PATTY_ERROR_H
+#define _PATTY_ERROR_H
+
+#define PATTY_ERROR_STRLEN 256
+
+enum patty_error_state {
+    PATTY_ERROR_OK,
+    PATTY_ERROR_SET
+};
+
+typedef struct _patty_error {
+    enum patty_error_state state;
+    char err[PATTY_ERROR_STRLEN];
+} patty_error;
+
+int patty_error_fmt(patty_error *e, const char *message, ...);
+
+void patty_error_clear(patty_error *e);
+
+int patty_error_set(patty_error *e);
+
+char *patty_error_string(patty_error *e);
+
+#endif /* _PATTY_ERROR_H */

src/Makefile

@@ -7,13 +7,13 @@ CC		= $(CROSS)cc
 CFLAGS		= $(CGFLAGS) -fPIC -Wall -O2 -I$(INCLUDE_PATH)
 LDFLAGS		= -lutil
 
-HEADERS		= kiss.h ax25.h client.h ax25/if.h ax25/frame.h \
-		  ax25/sock.h ax25/route.h ax25/server.h daemon.h list.h \
-		  hash.h dict.h timer.h print.h conf.h
+HEADERS		= kiss.h kiss/tnc.h ax25.h client.h ax25/if.h ax25/frame.h \
+		  ax25/sock.h ax25/route.h ax25/server.h daemon.h \
+		  error.h list.h hash.h dict.h timer.h print.h conf.h
 
-OBJS		= kiss.o ax25.o client.o if.o frame.o \
-		  sock.o route.o server.o daemon.o list.o \
-		  hash.o dict.o timer.o print.o conf.o
+OBJS		= kiss.o tnc.o ax25.o client.o if.o frame.o \
+		  sock.o route.o server.o daemon.o \
+		  error.o list.o hash.o dict.o timer.o print.o conf.o
 
 VERSION_MAJOR	= 0
 VERSION_MINOR	= 0.1

src/error.c

@@ -0,0 +1,41 @@
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+
+#include <patty/error.h>
+
+int patty_error_fmt(patty_error *e, const char *message, ...) {
+    va_list args;
+
+    va_start(args, message);
+
+    if (vsnprintf(e->err, sizeof(e->err)-1, message, args) < 0) {
+        goto error_vsnprintf;
+    }
+
+    va_end(args);
+
+    e->state = PATTY_ERROR_SET;
+
+    return 0;
+
+error_vsnprintf:
+    va_end(args);
+
+    return -1;
+}
+
+void patty_error_clear(patty_error *e) {
+    memset(e->err, '\0', sizeof(e->err));
+
+    e->state = PATTY_ERROR_OK;
+}
+
+int patty_error_isset(patty_error *e) {
+    return e->state == PATTY_ERROR_SET? 1: 0;
+}
+
+char *patty_error_string(patty_error *e) {
+    return e->err;
+}