Refactor & constify error logging code

Signed-off-by: Alan Coopersmith <alan.coopersmith@sun.com>

4 files changed, 71 insertions, 80 deletions

diff --git a/dm_error.h b/dm_error.h
index e32ba0b..739da7b 100644
--- a/dm_error.h
+++ b/dm_error.h
@@ -40,13 +40,13 @@ authorization.
 #  define GCC_PRINTFLIKE(fmt,var) /*nothing*/
 # endif
 
-extern void Debug        (char * fmt, ...) GCC_PRINTFLIKE(1,2);
+extern void Debug        (const char * fmt, ...) GCC_PRINTFLIKE(1,2);
 extern void InitErrorLog (void);
-extern void LogAppend    (char * fmt, ...) GCC_PRINTFLIKE(1,2);
-extern void LogError     (char * fmt, ...) GCC_PRINTFLIKE(1,2);
-extern void LogInfo      (char * fmt, ...) GCC_PRINTFLIKE(1,2);
-extern void LogOutOfMem  (char * fmt, ...) GCC_PRINTFLIKE(1,2);
-extern void LogPanic     (char * fmt, ...) GCC_PRINTFLIKE(1,2);
+extern void LogAppend    (const char * fmt, ...) GCC_PRINTFLIKE(1,2);
+extern void LogError     (const char * fmt, ...) GCC_PRINTFLIKE(1,2);
+extern void LogInfo      (const char * fmt, ...) GCC_PRINTFLIKE(1,2);
+extern void LogOutOfMem  (const char * fmt, ...) GCC_PRINTFLIKE(1,2);
+extern void LogPanic     (const char * fmt, ...) GCC_PRINTFLIKE(1,2);
 
 
 #endif /* _DM_ERROR_H_ */
diff --git a/error.c b/error.c
index f1cb951..d1bd16e 100644
--- a/error.c
+++ b/error.c
@@ -42,70 +42,63 @@ from The Open Group.
 #include "dm.h"
 #include "dm_error.h"
 
-#define WRITES(fd, buf) write(fd, buf, strlen(buf))
-
-/* Append more text to the log without a new header, right after
-   having called LogInfo or LogError */
-void LogAppend(char * fmt, ...)
+/* This function does the actual log message writes. */
+static inline void
+LogVWrite(const char *fmt, va_list args)
 {
     char buf[1024];
+    int len;
 
-    {
-	va_list args;
-	va_start(args, fmt);
-	vsnprintf (buf, sizeof buf, fmt, args);
-	va_end(args);
+    len = vsnprintf (buf, sizeof(buf), fmt, args);
+    if (len >= sizeof(buf)) {
+	len = sizeof(buf) - 1;
     }
-    WRITES(STDERR_FILENO, buf);
+    write(STDERR_FILENO, buf, len);
 }
 
-void LogInfo(char * fmt, ...)
-{
-    char buf[1024];
+#define LogVarArgsWrite(fmt)	\
+    do {			\
+	va_list args;		\
+	va_start(args, fmt);	\
+	LogVWrite(fmt, args);	\
+	va_end(args);		\
+    } while(0)
 
-    snprintf(buf, sizeof buf, "xdm info (pid %ld): ", (long)getpid());
-    WRITES(STDERR_FILENO, buf);
-    {
-	va_list args;
-	va_start(args, fmt);
-	vsnprintf (buf, sizeof buf, fmt, args);
-	va_end(args);
-    }
-    WRITES(STDERR_FILENO, buf);
-}
+#define LogHeader(type)		\
+    LogAppend("xdm %s (pid %ld): ", type, (long)getpid())
 
-void LogError (char * fmt, ...)
+/* Append more text to the log without a new header, right after
+   having called LogInfo or LogError */
+void
+LogAppend(const char * fmt, ...)
 {
-    char buf[1024];
+    LogVarArgsWrite(fmt);
+}
 
-    snprintf (buf, sizeof buf, "xdm error (pid %ld): ", (long)getpid());
-    WRITES(STDERR_FILENO, buf);
-    {
-	va_list args;
-	va_start(args, fmt);
-	vsnprintf (buf, sizeof buf, fmt, args);
-	va_end(args);
-    }
-    WRITES(STDERR_FILENO, buf);
+void
+LogInfo(const char * fmt, ...)
+{
+    LogHeader("info");
+    LogVarArgsWrite(fmt);
 }
 
-void LogPanic (char * fmt, ...)
+void
+LogError (const char * fmt, ...)
 {
-    char buf[1024];
+    LogHeader("error");
+    LogVarArgsWrite(fmt);
+}
 
-    snprintf (buf, sizeof buf, "xdm panic (pid %ld): ", (long)getpid());
-    WRITES(STDERR_FILENO, buf);
-    {
-	va_list args;
-	va_start(args, fmt);
-	vsnprintf (buf, sizeof buf, fmt, args);
-	va_end(args);
-    }
-    WRITES(STDERR_FILENO, buf);
+void
+LogPanic (const char * fmt, ...)
+{
+    LogHeader("panic");
+    LogVarArgsWrite(fmt);
     _exit (1);
 }
 
-void LogOutOfMem (char * fmt, ...)
+void
+LogOutOfMem (const char * fmt, ...)
 {
     fprintf (stderr, "xdm: out of memory in routine ");
     {
@@ -117,31 +110,29 @@ void LogOutOfMem (char * fmt, ...)
     fflush (stderr);
 }
 
-void Debug (char * fmt, ...)
+void
+Debug (const char * fmt, ...)
 {
     char buf[1024];
 
     if (debugLevel > 0)
     {
-	va_list args;
-	va_start(args, fmt);
-	vsnprintf (buf, sizeof buf, fmt, args);
-	va_end(args);
-	WRITES(STDOUT_FILENO, buf);
+	LogVarArgsWrite(fmt);
     }
 }
 
-void InitErrorLog (void)
+void
+InitErrorLog (void)
 {
-	int	i;
-	if (errorLogFile[0]) {
-		i = creat (errorLogFile, 0666);
-		if (i != -1) {
-			if (i != 2) {
-				dup2 (i, 2);
-				close (i);
-			}
-		} else
-			LogError ("Cannot open errorLogFile %s\n", errorLogFile);
-	}
+    int	i;
+    if (errorLogFile[0]) {
+	i = creat (errorLogFile, 0666);
+	if (i != -1) {
+	    if (i != STDERR_FILENO) {
+		dup2 (i, STDERR_FILENO);
+		close (i);
+	    }
+	} else
+	    LogError ("Cannot open errorLogFile %s\n", errorLogFile);
+    }
 }
diff --git a/greet.h b/greet.h
index ca6ee73..bf3ddd1 100644
--- a/greet.h
+++ b/greet.h
@@ -54,13 +54,13 @@ from The Open Group.
 struct dlfuncs {
     int (*_PingServer)(struct display *d, Display *alternateDpy);
     void (*_SessionPingFailed)(struct display *d);
-    void (*_Debug)(char * fmt, ...);
+    void (*_Debug)(const char * fmt, ...);
     void (*_RegisterCloseOnFork)(int fd);
     void (*_SecureDisplay)(struct display *d, Display *dpy);
     void (*_UnsecureDisplay)(struct display *d, Display *dpy);
     void (*_ClearCloseOnFork)(int fd);
     void (*_SetupDisplay)(struct display *d);
-    void (*_LogError)(char * fmt, ...);
+    void (*_LogError)(const char * fmt, ...);
     void (*_SessionExit)(struct display *d, int status, int removeAuth);
     void (*_DeleteXloginResources)(struct display *d, Display *dpy);
     int (*_source)(char **environ, char *file);
@@ -70,7 +70,7 @@ struct dlfuncs {
     char **(*_parseArgs)(char **argv, char *string);
     void (*_printEnv)(char **e);
     char **(*_systemEnv)(struct display *d, char *user, char *home);
-    void (*_LogOutOfMem)(char * fmt, ...);
+    void (*_LogOutOfMem)(const char * fmt, ...);
     SETGRENT_TYPE (*_setgrent)(void);		/* no longer used */
     struct group *(*_getgrent)(void);	/* no longer used */
     void (*_endgrent)(void);		/* no longer used */
@@ -138,13 +138,13 @@ typedef greet_user_rtn (*GreetUserProc)(struct display *, Display **,
 
 extern	int     (*__xdm_PingServer)(struct display *d, Display *alternateDpy);
 extern	void    (*__xdm_SessionPingFailed)(struct display *d);
-extern	void    (*__xdm_Debug)(char * fmt, ...);
+extern	void    (*__xdm_Debug)(const char * fmt, ...);
 extern	void    (*__xdm_RegisterCloseOnFork)(int fd);
 extern	void    (*__xdm_SecureDisplay)(struct display *d, Display *dpy);
 extern	void    (*__xdm_UnsecureDisplay)(struct display *d, Display *dpy);
 extern	void    (*__xdm_ClearCloseOnFork)(int fd);
 extern	void    (*__xdm_SetupDisplay)(struct display *d);
-extern	void    (*__xdm_LogError)(char * fmt, ...);
+extern	void    (*__xdm_LogError)(const char * fmt, ...);
 extern	void    (*__xdm_SessionExit)(struct display *d, int status, int removeAuth);
 extern	void    (*__xdm_DeleteXloginResources)(struct display *d, Display *dpy);
 extern	int     (*__xdm_source)(char **environ, char *file);
@@ -154,7 +154,7 @@ extern	char    **(*__xdm_putEnv)(const char *string, char **env);
 extern	char    **(*__xdm_parseArgs)(char **argv, char *string);
 extern	void    (*__xdm_printEnv)(char **e);
 extern	char    **(*__xdm_systemEnv)(struct display *d, char *user, char *home);
-extern	void    (*__xdm_LogOutOfMem)(char * fmt, ...);
+extern	void    (*__xdm_LogOutOfMem)(const char * fmt, ...);
 extern	void    (*__xdm_setgrent)(void);
 extern	struct group    *(*__xdm_getgrent)(void);
 extern	void    (*__xdm_endgrent)(void);
diff --git a/greeter/greet.c b/greeter/greet.c
index a4e799c..17d21c8 100644
--- a/greeter/greet.c
+++ b/greeter/greet.c
@@ -105,13 +105,13 @@ extern int getdomainname(char *name, size_t len);
 
 int     (*__xdm_PingServer)(struct display *d, Display *alternateDpy) = NULL;
 void    (*__xdm_SessionPingFailed)(struct display *d) = NULL;
-void    (*__xdm_Debug)(char * fmt, ...) = NULL;
+void    (*__xdm_Debug)(const char * fmt, ...) = NULL;
 void    (*__xdm_RegisterCloseOnFork)(int fd) = NULL;
 void    (*__xdm_SecureDisplay)(struct display *d, Display *dpy) = NULL;
 void    (*__xdm_UnsecureDisplay)(struct display *d, Display *dpy) = NULL;
 void    (*__xdm_ClearCloseOnFork)(int fd) = NULL;
 void    (*__xdm_SetupDisplay)(struct display *d) = NULL;
-void    (*__xdm_LogError)(char * fmt, ...) = NULL;
+void    (*__xdm_LogError)(const char * fmt, ...) = NULL;
 void    (*__xdm_SessionExit)(struct display *d, int status, int removeAuth) = NULL;
 void    (*__xdm_DeleteXloginResources)(struct display *d, Display *dpy) = NULL;
 int     (*__xdm_source)(char **environ, char *file) = NULL;
@@ -121,7 +121,7 @@ char    **(*__xdm_putEnv)(const char *string, char **env) = NULL;
 char    **(*__xdm_parseArgs)(char **argv, char *string) = NULL;
 void    (*__xdm_printEnv)(char **e) = NULL;
 char    **(*__xdm_systemEnv)(struct display *d, char *user, char *home) = NULL;
-void    (*__xdm_LogOutOfMem)(char * fmt, ...) = NULL;
+void    (*__xdm_LogOutOfMem)(const char * fmt, ...) = NULL;
 void    (*__xdm_setgrent)(void) = NULL;
 struct group    *(*__xdm_getgrent)(void) = NULL;
 void    (*__xdm_endgrent)(void) = NULL;