Implement send_mail

Signed-off-by: Colin McCabe <colin.mccabe@dreamhost.com>

diff --git a/handle_core.c b/handle_core.c
index 93d03cc..ce81772 100644 (file)
--- a/handle_core.c
+++ b/handle_core.c
@@ -1,10 +1,11 @@
 #include <ctype.h>
-#include <errno.h>
 #include <dirent.h>
+#include <errno.h>
 #include <fcntl.h>
 #include <fnmatch.h>
 #include <glob.h>
 #include <limits.h>
+#include <netdb.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
@@ -21,8 +22,9 @@
  * Core file handler
  *
  * Example usage:
- * echo "|/usr/bin/handle_core -e %e -d /home/core -m 10" > \
- *     /proc/sys/kernel/core_pattern
+ * echo "|/sbin/handle_core -e %e -d /var/core -m 10 \
+ *             -s '/usr/sbin/sendmail -t sysadmin@example.com'" > \
+ *                     /proc/sys/kernel/core_pattern
  */
 
 /* Count the number of core files we have. */
@@ -92,17 +94,20 @@ static void usage(void)
 -h                             This help message\n\
 -m <max_cores>                 This maximum number of core files to allow\n\
                                before deleting older core files.\n\
+-s <email_command>             Send email using email_command.\n\
+                               Example: -s '/usr/sbin/sendmail -t sysadmin@example.com'\n\
 ");
 }
 
 static int parse_options(int argc, char **argv, int *max_cores,
-                         char **exe_name, char **core_dir)
+                         char **exe_name, char **core_dir, char **email)
 {
        int c;
        *max_cores = 10;
        *exe_name = NULL;
        *core_dir = "/var/core";
-       while ((c = getopt(argc, argv, "d:e:hm:")) != -1) {
+       *email = NULL;
+       while ((c = getopt(argc, argv, "d:e:hm:s:")) != -1) {
                switch (c) {
                case 'd':
                        *core_dir = optarg;
@@ -123,6 +128,9 @@ static int parse_options(int argc, char **argv, int *max_cores,
                                return 1;
                        }
                        break;
+               case 's':
+                       *email = optarg;
+                       break;
                default:
                        fprintf(stderr, "handle_core: invalid usage\n\n");
                        return 1;
@@ -137,17 +145,61 @@ static int parse_options(int argc, char **argv, int *max_cores,
        return 0;
 }
 
+int send_mail(const char *exe_name, const char *core_dir,
+             const char *core_name, const char *email)
+{
+       char hostname[255];
+       struct hostent *fqdn;
+       const char *fqdn_name;
+       FILE *fp;
+
+       if (!email)
+               return 0;
+       fp = popen(email, "w");
+       if (!fp) {
+               int err = errno;
+               syslog(LOG_USER | LOG_ERR, "popen(%s) error: %d (%s)",
+                       email, err, strerror(err));
+               return err;
+       }
+       if (gethostname(hostname, sizeof(hostname))) {
+               int err = errno;
+               syslog(LOG_USER | LOG_ERR, "gethostname error: %d (%s)",
+                       err, strerror(err));
+               snprintf(hostname, sizeof(hostname), "(unknown-host)");
+       }
+       fqdn = gethostbyname(hostname);
+       if (!fqdn) {
+               int err = h_errno;
+               syslog(LOG_USER | LOG_ERR, "gethostbyname(%s) error: %d",
+                       hostname, err);
+               fqdn_name = hostname;
+       }
+       else {
+               fqdn_name = fqdn->h_name;
+       }
+       fprintf(fp, "\
+Subject: [core_dump] %s crashed on %s\r\n\r\n\
+!!!!! Crash encountered on %s !!!!!!!!!\r\n\
+executable name: %s\r\n\
+core file name: %s/%s\r\n\
+", exe_name, hostname, fqdn_name, exe_name, core_dir, core_name);
+       fclose(fp);
+       return 0;
+}
+
 int main(int argc, char **argv)
 {
        int ret, done = 0;
-       char *exe_name, *core_dir;
+       char *exe_name, *core_dir, *email;
        char core_name[PATH_MAX];
        FILE *fp;
        int num_coref, num_deleted;
        int max_cores;
 
        /* Write the core to a file */
-       ret = parse_options(argc, argv, &max_cores, &exe_name, &core_dir);
+       ret = parse_options(argc, argv, &max_cores, &exe_name, &core_dir,
+                           &email);
        if (ret) {
                syslog(LOG_USER | LOG_ERR, "parse_options error\n");
                return 1;
@@ -205,6 +257,12 @@ int main(int argc, char **argv)
                num_deleted++;
        }
 
+       ret = send_mail(exe_name, core_dir, core_name, email);
+       if (ret) {
+               syslog(LOG_USER | LOG_ERR, "send_mail failed with error "
+                      "code %d\n", ret);
+       }
+
        syslog(LOG_USER | LOG_ERR, "wrote core %s. Deleted %d extra core%s\n",
               core_name, num_deleted, ((num_deleted == 1) ? "" : "s"));
        return 0;