crond: tweak help text, make course less cryptic

function                                             old     new   delta
packed_usage                                       29736   29740      +4
crond_main                                          1485    1486      +1
load_crontab                                         712     706      -6

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>

3 files changed, 68 insertions, 61 deletions

diff --git a/miscutils/Config.src b/miscutils/Config.src
index 1da9800bd..1b2a3ae9a 100644
--- a/miscutils/Config.src
+++ b/miscutils/Config.src
@@ -133,40 +133,6 @@ config CHRT
           manipulate real-time attributes of a process.
           This requires sched_{g,s}etparam support in your libc.
 
-config CROND
-        bool "crond"
-        default y
-        select FEATURE_SYSLOG
-        help
-          Crond is a background daemon that parses individual crontab
-          files and executes commands on behalf of the users in question.
-          This is a port of dcron from slackware. It uses files of the
-          format /var/spool/cron/crontabs/<username> files, for example:
-              $ cat /var/spool/cron/crontabs/root
-              # Run daily cron jobs at 4:40 every day:
-              40 4 * * * /etc/cron/daily > /dev/null 2>&1
-
-config FEATURE_CROND_D
-        bool "Support option -d to redirect output to stderr"
-        depends on CROND
-        default y
-        help
-          -d sets loglevel to 0 (most verbose) and directs all output to stderr.
-
-config FEATURE_CROND_CALL_SENDMAIL
-        bool "Report command output via email (using sendmail)"
-        default y
-        depends on CROND
-        help
-          Command output will be sent to corresponding user via email.
-
-config FEATURE_CROND_DIR
-        string "crond spool directory"
-        default "/var/spool/cron"
-        depends on CROND || CRONTAB
-        help
-          Location of crond spool.
-
 config CRONTAB
         bool "crontab"
         default y
diff --git a/miscutils/Kbuild.src b/miscutils/Kbuild.src
index 9e164f16e..8eaa82de9 100644
--- a/miscutils/Kbuild.src
+++ b/miscutils/Kbuild.src
@@ -12,7 +12,6 @@ lib-$(CONFIG_BBCONFIG)    += bbconfig.o
 lib-$(CONFIG_BEEP)        += beep.o
 lib-$(CONFIG_CHAT)        += chat.o
 lib-$(CONFIG_CHRT)        += chrt.o
-lib-$(CONFIG_CROND)       += crond.o
 lib-$(CONFIG_CRONTAB)     += crontab.o
 lib-$(CONFIG_DC)          += dc.o
 lib-$(CONFIG_DEVFSD)      += devfsd.o
diff --git a/miscutils/crond.c b/miscutils/crond.c
index 582dc991a..995ed9e0a 100644
--- a/miscutils/crond.c
+++ b/miscutils/crond.c
@@ -1,7 +1,5 @@
 /* vi: set sw=4 ts=4: */
 /*
- * crond -d[#] -c <crondir> -f -b
- *
  * run as root, but NOT setuid root
  *
  * Copyright 1994 Matthew Dillon (dillon@apollo.west.oic.com)
@@ -10,6 +8,43 @@
  *
  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  */
+//config:config CROND
+//config:       bool "crond"
+//config:       default y
+//config:       select FEATURE_SYSLOG
+//config:       help
+//config:         Crond is a background daemon that parses individual crontab
+//config:         files and executes commands on behalf of the users in question.
+//config:         This is a port of dcron from slackware. It uses files of the
+//config:         format /var/spool/cron/crontabs/<username> files, for example:
+//config:             $ cat /var/spool/cron/crontabs/root
+//config:             # Run daily cron jobs at 4:40 every day:
+//config:             40 4 * * * /etc/cron/daily > /dev/null 2>&1
+//config:
+//config:config FEATURE_CROND_D
+//config:       bool "Support option -d to redirect output to stderr"
+//config:       depends on CROND
+//config:       default y
+//config:       help
+//config:         -d N sets loglevel (0:most verbose) and directs all output to stderr.
+//config:
+//config:config FEATURE_CROND_CALL_SENDMAIL
+//config:       bool "Report command output via email (using sendmail)"
+//config:       default y
+//config:       depends on CROND
+//config:       help
+//config:         Command output will be sent to corresponding user via email.
+//config:
+//config:config FEATURE_CROND_DIR
+//config:       string "crond spool directory"
+//config:       default "/var/spool/cron"
+//config:       depends on CROND || CRONTAB
+//config:       help
+//config:         Location of crond spool.
+
+//applet:IF_CROND(APPLET(crond, BB_DIR_USR_SBIN, BB_SUID_DROP))
+
+//kbuild:lib-$(CONFIG_CROND) += crond.o
 
 //usage:#define crond_trivial_usage
 //usage:       "-fbS -l N " IF_FEATURE_CROND_D("-d N ") "-L LOGFILE -c DIR"
@@ -17,12 +52,12 @@
 //usage:       "        -f      Foreground"
 //usage:     "\n        -b      Background (default)"
 //usage:     "\n        -S      Log to syslog (default)"
-//usage:     "\n        -l      Set log level. 0 is the most verbose, default 8"
+//usage:     "\n        -l N    Set log level. Most verbose:0, default:8"
 //usage:        IF_FEATURE_CROND_D(
-//usage:     "\n        -d      Set log level, log to stderr"
+//usage:     "\n        -d N    Set log level, log to stderr"
 //usage:        )
-//usage:     "\n        -L      Log to file"
-//usage:     "\n        -c      Working dir"
+//usage:     "\n        -L FILE Log to FILE"
+//usage:     "\n        -c DIR  Cron dir. Default:"CONFIG_FEATURE_CROND_DIR"/crontabs"
 
 #include "libbb.h"
 #include <syslog.h>
@@ -36,7 +71,7 @@
 #endif
 
 
-#define TMPDIR          CONFIG_FEATURE_CROND_DIR
+#define CRON_DIR        CONFIG_FEATURE_CROND_DIR
 #define CRONTABS        CONFIG_FEATURE_CROND_DIR "/crontabs"
 #ifndef SENDMAIL
 # define SENDMAIL       "sendmail"
@@ -158,12 +193,10 @@ static void crondlog(const char *ctl, ...)
 
 static const char DowAry[] ALIGN1 =
         "sun""mon""tue""wed""thu""fri""sat"
-        /* "Sun""Mon""Tue""Wed""Thu""Fri""Sat" */
 ;
 
 static const char MonAry[] ALIGN1 =
         "jan""feb""mar""apr""may""jun""jul""aug""sep""oct""nov""dec"
-        /* "Jan""Feb""Mar""Apr""May""Jun""Jul""Aug""Sep""Oct""Nov""Dec" */
 ;
 
 static void ParseField(char *user, char *ary, int modvalue, int off,
@@ -393,8 +426,11 @@ static void load_crontab(const char *fileName)
                 while (1) {
                         CronLine *line;
 
-                        if (!--maxLines)
+                        if (!--maxLines) {
+                                crondlog(WARN9 "user %s: too many lines", fileName);
                                 break;
+                        }
+
                         n = config_read(parser, tokens, 6, 1, "# \t", PARSE_NORMAL | PARSE_KEEP_COPY);
                         if (!n)
                                 break;
@@ -410,6 +446,18 @@ static void load_crontab(const char *fileName)
 #endif /* otherwise just ignore such lines */
                                 continue;
                         }
+//TODO: handle SHELL=, HOME= too? "man crontab" says:
+//name = value
+//
+//where the spaces around the equal-sign (=) are optional, and any subsequent
+//non-leading spaces in value will be part of the value assigned to name.
+//The value string may be placed in quotes (single or double, but matching)
+//to preserve leading or trailing blanks.
+//
+//Several environment variables are set up automatically by the cron(8) daemon.
+//SHELL is set to /bin/sh, and LOGNAME and HOME are set from the /etc/passwd
+//line of the crontab's owner. HOME and SHELL may be overridden by settings
+//in the crontab; LOGNAME may not.
                         /* check if a minimum of tokens is specified */
                         if (n < 6)
                                 continue;
@@ -441,10 +489,6 @@ static void load_crontab(const char *fileName)
 
                 file->cf_next = G.cron_files;
                 G.cron_files = file;
-
-                if (maxLines == 0) {
-                        crondlog(WARN9 "user %s: too many lines", fileName);
-                }
         }
         config_close(parser);
 }
@@ -540,8 +584,8 @@ static void change_user(struct passwd *pas)
         change_identity(pas); /* - initgroups, setgid, setuid */
         if (chdir(pas->pw_dir) < 0) {
                 crondlog(WARN9 "chdir(%s)", pas->pw_dir);
-                if (chdir(TMPDIR) < 0) {
-                        crondlog(DIE9 "chdir(%s)", TMPDIR); /* exits */
+                if (chdir(CRON_DIR) < 0) {
+                        crondlog(DIE9 "chdir(%s)", CRON_DIR); /* exits */
                 }
         }
 }
@@ -568,7 +612,7 @@ fork_job(const char *user, int mailFd,
         pid = vfork();
         if (pid == 0) {
                 /* CHILD */
-                /* initgroups, setgid, setuid, and chdir to home or TMPDIR */
+                /* initgroups, setgid, setuid, and chdir to home or CRON_DIR */
                 change_user(pas);
                 if (DebugOpt) {
                         crondlog(LVL5 "child running %s", prog);
@@ -588,7 +632,6 @@ fork_job(const char *user, int mailFd,
         }
 
         if (pid < 0) {
-                /* FORK FAILED */
                 crondlog(ERR20 "can't vfork");
  err:
                 pid = 0;
@@ -614,7 +657,7 @@ static void start_one_job(const char *user, CronLine *line)
 
         if (line->cl_mailto) {
                 /* Open mail file (owner is root so nobody can screw with it) */
-                snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", TMPDIR, user, getpid());
+                snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", CRON_DIR, user, getpid());
                 mailFd = open(mailFile, O_CREAT | O_TRUNC | O_WRONLY | O_EXCL | O_APPEND, 0600);
 
                 if (mailFd >= 0) {
@@ -633,7 +676,7 @@ static void start_one_job(const char *user, CronLine *line)
                         unlink(mailFile);
                 } else {
                         /* rename mail-file based on pid of process */
-                        char *mailFile2 = xasprintf("%s/cron.%s.%d", TMPDIR, user, (int)line->cl_pid);
+                        char *mailFile2 = xasprintf("%s/cron.%s.%d", CRON_DIR, user, (int)line->cl_pid);
                         rename(mailFile, mailFile2); // TODO: xrename?
                         free(mailFile2);
                 }
@@ -665,7 +708,7 @@ static void process_finished_job(const char *user, CronLine *line)
          * End of primary job - check for mail file.
          * If size has changed and the file is still valid, we send it.
          */
-        snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", TMPDIR, user, (int)pid);
+        snprintf(mailFile, sizeof(mailFile), "%s/cron.%s.%d", CRON_DIR, user, (int)pid);
         mailFd = open(mailFile, O_RDONLY);
         unlink(mailFile);
         if (mailFd < 0) {
@@ -706,7 +749,7 @@ static void start_one_job(const char *user, CronLine *line)
         pid = vfork();
         if (pid == 0) {
                 /* CHILD */
-                /* initgroups, setgid, setuid, and chdir to home or TMPDIR */
+                /* initgroups, setgid, setuid, and chdir to home or CRON_DIR */
                 change_user(pas);
                 if (DebugOpt) {
                         crondlog(LVL5 "child running %s", DEFAULT_SHELL);
@@ -853,8 +896,8 @@ int crond_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 int crond_main(int argc UNUSED_PARAM, char **argv)
 {
         time_t t2;
-        int rescan;
-        int sleep_time;
+        unsigned rescan;
+        unsigned sleep_time;
         unsigned opts;
 
         INIT_G();
@@ -940,11 +983,10 @@ int crond_main(int argc UNUSED_PARAM, char **argv)
                         /* Usual case: time advances forward, as expected */
                         flag_starting_jobs(t1, t2);
                         start_jobs();
+                        sleep_time = 60;
                         if (check_completions() > 0) {
                                 /* some jobs are still running */
                                 sleep_time = 10;
-                        } else {
-                                sleep_time = 60;
                         }
                 }
                 /* else: time jumped back, do not run any jobs */