refactor code

Added common functions autoconf_check_readable and fail.
Added some TODOs for later completion.
Updated messages from upstream plugins.

tools/munin-plugins-busybox/common.c

@@ -1,3 +1,4 @@
+#include <errno.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -10,12 +11,13 @@ int writeyes(void) {
 	return 0;
 }
 
-int writeno(const char *s) {
-	if(s)
-		printf("no (%s)\n", s);
-	else
-		puts("no");
+int autoconf_check_readable(const char *path) {
+	if(0 == access(path, R_OK))
+		return writeyes();
+	else {
+		printf("no (%s is not readable, errno=%d)\n", path, errno);
 		return 1;
+	}
 }
 
 int getenvint(const char *name, int defvalue) {
@@ -64,3 +66,9 @@ void print_warncrit(const char *name) {
 	print_warning(name);
 	print_critical(name);
 }
+
+int fail(const char *message) {
+	fputs(message, stderr);
+	fputc('\n', stderr);
+	return 1;
+}

tools/munin-plugins-busybox/common.h

@@ -4,11 +4,12 @@
 #define PROC_STAT "/proc/stat"
 
 int writeyes(void);
-int writeno(const char *);
+int autoconf_check_readable(const char *);
 int getenvint(const char *, int);
 const char *getenv_composed(const char *, const char *);
 void print_warning(const char *);
 void print_critical(const char *);
 void print_warncrit(const char *);
+int fail(const char *);
 
 #endif

tools/munin-plugins-busybox/cpu.c

@@ -9,6 +9,8 @@
 #define SYSCRITICAL 50
 #define USRWARNING 80
 
+/* TODO: port support for env.foo_warning and env.foo_critical from mainline plugin */
+
 int cpu(int argc, char **argv) {
 	FILE *f;
 	char buff[256], *s;
@@ -19,10 +21,8 @@ int cpu(int argc, char **argv) {
 			if(s && !strcmp(s, "yes"))
 				scaleto100=1;
 
-			if(!(f=fopen(PROC_STAT, "r"))) {
-				fputs("cannot open " PROC_STAT "\n", stderr);
-				return 1;
-			}
+			if(!(f=fopen(PROC_STAT, "r")))
+				return fail("cannot open " PROC_STAT);
 			while(fgets(buff, 256, f)) {
 				if(!strncmp(buff, "cpu", 3)) {
 					if(isdigit(buff[3]))
@@ -36,10 +36,8 @@ int cpu(int argc, char **argv) {
 			}
 			fclose(f);
 
-			if(ncpu < 1 || extinfo < 4) {
-				fputs("cannot parse " PROC_STAT "\n", stderr);
-				return 1;
-			}
+			if(ncpu < 1 || extinfo < 4)
+				return fail("cannot parse " PROC_STAT);
 
 			puts("graph_title CPU usage");
 			if(extinfo >= 7)
@@ -133,17 +131,11 @@ int cpu(int argc, char **argv) {
 			}
 			return 0;
 		}
-		if(!strcmp(argv[1], "autoconf")) {
-			if(0 == access(PROC_STAT, R_OK))
-				return writeyes();
-			else
-				return writeno(PROC_STAT " not readable");
-		}
-	}
-	if(!(f=fopen(PROC_STAT, "r"))) {
-		fputs("cannot open " PROC_STAT "\n", stderr);
-		return 1;
+		if(!strcmp(argv[1], "autoconf"))
+			return autoconf_check_readable(PROC_STAT);
 	}
+	if(!(f=fopen(PROC_STAT, "r")))
+		return fail("cannot open " PROC_STAT);
 	while(fgets(buff, 256, f)) {
 		hz = getenvint("HZ", 100);
 		if(!strncmp(buff, "cpu ", 4)) {
@@ -179,6 +171,5 @@ int cpu(int argc, char **argv) {
 		}
 	}
 	fclose(f);
-	fputs("no cpu line found in " PROC_STAT "\n", stderr);
-	return 1;
+	return fail("no cpu line found in " PROC_STAT);
 }

tools/munin-plugins-busybox/entropy.c

@@ -1,5 +1,6 @@
 #include <string.h>
 #include <stdio.h>
+#include <unistd.h>
 #include "common.h"
 
 #define ENTROPY_AVAIL "/proc/sys/kernel/random/entropy_avail"
@@ -21,16 +22,13 @@ int entropy(int argc, char **argv) {
 			return 0;
 		}
 		if(!strcmp(argv[1], "autoconf"))
-			return writeyes();
-	}
-	if(!(f=fopen(ENTROPY_AVAIL, "r"))) {
-		fputs("cannot open " ENTROPY_AVAIL "\n", stderr);
-		return 1;
+			return autoconf_check_readable(ENTROPY_AVAIL);
 	}
+	if(!(f=fopen(ENTROPY_AVAIL, "r")))
+		return fail("cannot open " ENTROPY_AVAIL);
 	if(1 != fscanf(f, "%d", &entropy)) {
-		fputs("cannot read from " ENTROPY_AVAIL "\n", stderr);
 		fclose(f);
-		return 1;
+		return fail("cannot read from " ENTROPY_AVAIL);
 	}
 	fclose(f);
 	printf("entropy.value %d\n", entropy);

tools/munin-plugins-busybox/forks.c

@@ -21,17 +21,11 @@ int forks(int argc, char **argv) {
 			print_warncrit("forks");
 			return 0;
 		}
-		if(!strcmp(argv[1], "autoconf")) {
-			if(0 == access(PROC_STAT, R_OK))
-				return writeyes();
-			else
-				return writeno(PROC_STAT " not readable");
-		}
-	}
-	if(!(f=fopen(PROC_STAT, "r"))) {
-		fputs("cannot open " PROC_STAT "\n", stderr);
-		return 1;
+		if(!strcmp(argv[1], "autoconf"))
+			return autoconf_check_readable(PROC_STAT);
 	}
+	if(!(f=fopen(PROC_STAT, "r")))
+		return fail("cannot open " PROC_STAT);
 	while(fgets(buff, 256, f)) {
 		if(!strncmp(buff, "processes ", 10)) {
 			fclose(f);
@@ -40,6 +34,5 @@ int forks(int argc, char **argv) {
 		}
 	}
 	fclose(f);
-	fputs("no processes line found in " PROC_STAT "\n", stderr);
-	return 1;
+	return fail("no processes line found in " PROC_STAT);
 }

tools/munin-plugins-busybox/fw_packets.c

@@ -25,17 +25,11 @@ int fw_packets(int argc, char **argv) {
 				"forwarded.min 0");
 			return 0;
 		}
-		if(!strcmp(argv[1], "autoconf")) {
-			if(0 == access(PROC_NET_SNMP, R_OK))
-				return writeyes();
-			else
-				return writeno(PROC_NET_SNMP " not readable");
-		}
-	}
-	if(!(f=fopen(PROC_NET_SNMP, "r"))) {
-		fputs("cannot open " PROC_NET_SNMP "\n", stderr);
-		return 1;
+		if(!strcmp(argv[1], "autoconf"))
+			return autoconf_check_readable(PROC_NET_SNMP);
 	}
+	if(!(f=fopen(PROC_NET_SNMP, "r")))
+		return fail("cannot open " PROC_NET_SNMP);
 	while(fgets(buff, 1024, f)) {
 		if(!strncmp(buff, "Ip: ", 4) && isdigit(buff[4])) {
 			fclose(f);
@@ -57,6 +51,5 @@ int fw_packets(int argc, char **argv) {
 		}
 	}
 	fclose(f);
-	fputs("no ip line found in " PROC_NET_SNMP "\n", stderr);
-	return 1;
+	return fail("no ip line found in " PROC_NET_SNMP);
 }

tools/munin-plugins-busybox/if_err_.c

@@ -9,27 +9,20 @@
 
 int if_err_(int argc, char **argv) {
 	char *interface;
+	size_t interface_len;
 	FILE *f;
 	char buff[256], *s;
 	int i;
 
 	interface = basename(argv[0]);
-	if(strncmp(interface, "if_err_", 7) != 0) {
-		fputs("if_err_ invoked with invalid basename\n", stderr);
-		return 1;
-	}
+	if(strncmp(interface, "if_err_", 7) != 0)
+		return fail("if_err_ invoked with invalid basename");
 	interface += 7;
+	interface_len = strlen(interface);
 
 	if(argc > 1) {
-		if(!strcmp(argv[1], "autoconf")) {
-			if(access(PROC_NET_DEV, R_OK) == 0) {
-				puts("yes");
-				return 0;
-			} else {
-				puts("no (/proc/net/dev not found)");
-				return 1;
-			}
-		}
+		if(!strcmp(argv[1], "autoconf"))
+			return autoconf_check_readable(PROC_NET_DEV);
 		if(!strcmp(argv[1], "suggest")) {
 			if(NULL == (f = fopen(PROC_NET_DEV, "r")))
 				return 1;
@@ -83,9 +76,9 @@ int if_err_(int argc, char **argv) {
 	while(fgets(buff, 256, f)) {
 		for(s=buff;*s == ' ';++s)
 			;
-		if(0 != strncmp(s, interface, strlen(interface)))
+		if(0 != strncmp(s, interface, interface_len))
 			continue;
-		s += strlen(interface);
+		s += interface_len;
 		if(*s != ':')
 			continue;
 		++s;

tools/munin-plugins-busybox/interrupts.c

@@ -8,7 +8,7 @@ int interrupts(int argc, char **argv) {
 	char buff[256];
 	if(argc > 1) {
 		if(!strcmp(argv[1], "config")) {
-			puts("graph_title Interrupts & context switches\n"
+			puts("graph_title Interrupts and context switches\n"
 				"graph_args --base 1000 -l 0\n"
 				"graph_vlabel interrupts & ctx switches / ${graph_period}\n"
 				"graph_category system\n"
@@ -27,17 +27,11 @@ int interrupts(int argc, char **argv) {
 			print_warncrit("ctx");
 			return 0;
 		}
-		if(!strcmp(argv[1], "autoconf")) {
-			if(0 == access(PROC_STAT, R_OK))
-				return writeyes();
-			else
-				return writeno(PROC_STAT " not readable");
-		}
-	}
-	if(!(f=fopen(PROC_STAT, "r"))) {
-		fputs("cannot open " PROC_STAT "\n", stderr);
-		return 1;
+		if(!strcmp(argv[1], "autoconf"))
+			return autoconf_check_readable(PROC_STAT);
 	}
+	if(!(f=fopen(PROC_STAT, "r")))
+		return fail("cannot open " PROC_STAT);
 	while(fgets(buff, 256, f)) {
 		if(!strncmp(buff, "intr ", 5)) {
 			buff[5 + strcspn(buff + 5, " \t\n")] = '\0';

tools/munin-plugins-busybox/load.c

@@ -17,19 +17,18 @@ int load(int argc, char **argv) {
 				"graph_category system\n"
 				"load.label load");
 			print_warncrit("load");
+			puts("graph_info The load average of the machine describes how many processes are in the run-queue (scheduled to run \"immediately\").\n"
+				"load.info 5 minute load average");
 			return 0;
 		}
 		if(!strcmp(argv[1], "autoconf"))
 			return writeyes();
 	}
-	if(!(f=fopen(PROC_LOADAVG, "r"))) {
-		fputs("cannot open " PROC_LOADAVG "\n", stderr);
-		return 1;
-	}
+	if(!(f=fopen(PROC_LOADAVG, "r")))
+		return fail("cannot open " PROC_LOADAVG);
 	if(1 != fscanf(f, "%*f %f", &val)) {
-		fputs("cannot read from " PROC_LOADAVG "\n", stderr);
 		fclose(f);
-		return 1;
+		return fail("cannot read from " PROC_LOADAVG);
 	}
 	fclose(f);
 	printf("load.value %.2f\n", val);

tools/munin-plugins-busybox/main.c

@@ -1,6 +1,7 @@
 #include <libgen.h>
 #include <string.h>
 #include <stdio.h>
+#include "common.h"
 
 int cpu(int argc, char **argv);
 int entropy(int argc, char **argv);
@@ -16,14 +17,10 @@ int swap(int argc, char **argv);
 int uptime(int argc, char **argv);
 
 int busybox(int argc, char **argv) {
-	if(argc < 2) {
-		fprintf(stderr, "missing parameter\n");
-		return 1;
-	}
-	if(0 != strcmp(argv[1], "listplugins")) {
-		fprintf(stderr, "unknown parameter\n");
-		return 1;
-	}
+	if(argc < 2)
+		return fail("missing parameter");
+	if(0 != strcmp(argv[1], "listplugins"))
+		return fail("unknown parameter");
 	puts("cpu\nentropy\nforks\nfw_packets\ninterrupts\nload\n"
 		"open_files\nopen_inodes\nprocesses\nswap\nuptime");
 	return 0;
@@ -80,6 +77,5 @@ int main(int argc, char **argv) {
 				return uptime(argc, argv);
 			break;
 	}
-	fprintf(stderr, "unknown basename\n");
-	return 1;
+	return fail("unknown basename");
 }

tools/munin-plugins-busybox/open_files.c

@@ -5,20 +5,18 @@
 
 #define FS_FILE_NR "/proc/sys/fs/file-nr"
 
+/* TODO: support env.warning and friends after the upstream plugin is fixed */
+
 int open_files(int argc, char **argv) {
 	FILE *f;
 	int alloc, freeh, avail;
 	if(argc > 1) {
 		if(!strcmp(argv[1], "config")) {
-			if(!(f=fopen(FS_FILE_NR, "r"))) {
-				fprintf(stderr, "cannot open " FS_FILE_NR "\n");
-				return 1;
-			}
+			if(!(f=fopen(FS_FILE_NR, "r")))
+				return fail("cannot open " FS_FILE_NR);
 			if(1 != fscanf(f, "%*d %*d %d", &avail)) {
 				fclose(f);
-				fprintf(stderr, "cannot read from " FS_FILE_NR
-						"\n");
-				return 1;
+				return fail("cannot read from " FS_FILE_NR);
 			}
 			fclose(f);
 			puts("graph_title File table usage\n"
@@ -36,21 +34,14 @@ int open_files(int argc, char **argv) {
 					(int)(avail*0.92), (int)(avail*0.98));
 			return 0;
 		}
-		if(!strcmp(argv[1], "autoconf")) {
-			if(0 == access(FS_FILE_NR, R_OK))
-				return writeyes();
-			else
-				return writeno(FS_FILE_NR " not readable");
-		}
-	}
-	if(!(f=fopen(FS_FILE_NR, "r"))) {
-		fputs("cannot open " FS_FILE_NR "\n", stderr);
-		return 1;
+		if(!strcmp(argv[1], "autoconf"))
+			return autoconf_check_readable(FS_FILE_NR);
 	}
+	if(!(f=fopen(FS_FILE_NR, "r")))
+		return fail("cannot open " FS_FILE_NR);
 	if(3 != fscanf(f, "%d %d %d", &alloc, &freeh, &avail)) {
 		fclose(f);
-		fputs("cannot read from " FS_FILE_NR "\n", stderr);
-		return 1;
+		return fail("cannot read from " FS_FILE_NR);
 	}
 	fclose(f);
 	printf("used.value %d\nmax.value %d\n", alloc-freeh, avail);

tools/munin-plugins-busybox/open_inodes.c

@@ -23,21 +23,14 @@ int open_inodes(int argc, char **argv) {
 			print_warncrit("max");
 			return 0;
 		}
-		if(!strcmp(argv[1], "autoconf")) {
-			if(0 == access(FS_INODE_NR, R_OK))
-				return writeyes();
-			else
-				return writeno(FS_INODE_NR " not readable");
-		}
-	}
-	if(!(f=fopen(FS_INODE_NR, "r"))) {
-		fputs("cannot open " FS_INODE_NR "\n", stderr);
-		return 1;
+		if(!strcmp(argv[1], "autoconf"))
+			return autoconf_check_readable(FS_INODE_NR);
 	}
+	if(!(f=fopen(FS_INODE_NR, "r")))
+		return fail("cannot open " FS_INODE_NR);
 	if(2 != fscanf(f, "%d %d", &nr, &freen)) {
 		fclose(f);
-		fputs("cannot read from " FS_INODE_NR "\n", stderr);
-		return 1;
+		return fail("cannot read from " FS_INODE_NR);
 	}
 	fclose(f);
 	printf("used.value %d\nmax.value %d\n", nr-freen, nr);

tools/munin-plugins-busybox/processes.c

@@ -25,10 +25,8 @@ int processes(int argc, char **argv) {
 		if(!strcmp(argv[1], "autoconf"))
 			return writeyes();
 	}
-	if(!(d = opendir("/proc"))) {
-		fputs("cannot open /proc\n", stderr);
-		return 1;
-	}
+	if(!(d = opendir("/proc")))
+		return fail("cannot open /proc");
 	while((e = readdir(d))) {
 		for(s=e->d_name;*s;++s)
 			if(!isdigit(*s))

tools/munin-plugins-busybox/swap.c

@@ -27,19 +27,13 @@ int swap(int argc, char **argv) {
 			print_warncrit("swap_out");
 			return 0;
 		}
-		if(!strcmp(argv[1], "autoconf")) {
-			if(0 == access(PROC_STAT, R_OK))
-				return writeyes();
-			else
-				return writeno(PROC_STAT " not readable");
-		}
+		if(!strcmp(argv[1], "autoconf"))
+			return autoconf_check_readable(PROC_STAT);
 	}
 	if(!access("/proc/vmstat", F_OK)) {
 		in=out=0;
-		if(!(f=fopen("/proc/vmstat", "r"))) {
-			fputs("cannot open /proc/vmstat\n", stderr);
-			return 1;
-		}
+		if(!(f=fopen("/proc/vmstat", "r")))
+			return fail("cannot open /proc/vmstat");
 		while(fgets(buff, 256, f)) {
 			if(!in && !strncmp(buff, "pswpin ", 7)) {
 				++in;
@@ -51,30 +45,22 @@ int swap(int argc, char **argv) {
 			}
 		}
 		fclose(f);
-		if(!(in*out)) {
-			fputs("no usable data on /proc/vmstat\n", stderr);
-			return 1;
-		}
+		if(!(in*out))
+			return fail("no usable data on /proc/vmstat");
 		return 0;
 	} else {
-		if(!(f=fopen(PROC_STAT, "r"))) {
-			fputs("cannot open " PROC_STAT "\n", stderr);
-			return 1;
-		}
+		if(!(f=fopen(PROC_STAT, "r")))
+			return fail("cannot open " PROC_STAT);
 		while(fgets(buff, 256, f)) {
 			if(!strncmp(buff, "swap ", 5)) {
 				fclose(f);
-				if(2 != sscanf(buff+5, "%d %d", &in, &out)) {
-					fputs("bad data on " PROC_STAT "\n",
-							stderr);
-					return 1;
-				}
+				if(2 != sscanf(buff+5, "%d %d", &in, &out))
+					return fail("bad data on " PROC_STAT);
 				printf("swap_in.value %d\nswap_out.value %d\n", in, out);
 				return 0;
 			}
 		}
 		fclose(f);
-		fputs("no swap line found in " PROC_STAT "\n", stderr);
-		return 1;
+		return fail("no swap line found in " PROC_STAT);
 	}
 }

tools/munin-plugins-busybox/uptime.c

@@ -18,14 +18,11 @@ int uptime(int argc, char **argv) {
 		if(!strcmp(argv[1], "autoconf"))
 			return writeyes();
 	}
-	if(!(f=fopen("/proc/uptime", "r"))) {
-		fputs("cannot open /proc/uptime\n", stderr);
-		return 1;
-	}
+	if(!(f=fopen("/proc/uptime", "r")))
+		return fail("cannot open /proc/uptime");
 	if(1 != fscanf(f, "%f", &uptime)) {
-		fputs("cannot read from /proc/uptime\n", stderr);
 		fclose(f);
-		return 1;
+		return fail("cannot read from /proc/uptime");
 	}
 	fclose(f);
 	printf("uptime.value %.2f\n", uptime/86400);