new libbb func: xmalloc_realpath (+ use it where makes sense)

syslogd, logread: add debugging code (disabled)
syslogs: drastically smaller bss; fix "-C n" behaviour

diff --git a/coreutils/realpath.c b/coreutils/realpath.c
index 5f3242fb5c7e35a0c8abbb085a31915301037c90..7fac471eb547e90431e41346f2436c300574cf60 100644 (file)
--- a/coreutils/realpath.c
+++ b/coreutils/realpath.c
@@ -10,8 +10,6 @@
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
-#include <limits.h>
-#include <stdlib.h>
 #include "busybox.h"
 
 int realpath_main(int argc, char **argv)

diff --git a/include/libbb.h b/include/libbb.h
index 7ee66dce6df5ca3c7d7234eecab8376419b79692..e92e4db1c0b73a9e315cf37a6e1daa582e4c447f 100644 (file)
--- a/include/libbb.h
+++ b/include/libbb.h
@@ -238,6 +238,7 @@ extern DIR *warn_opendir(const char *path);
 
 char *xgetcwd(char *cwd);
 char *xreadlink(const char *path);
+char *xmalloc_realpath(const char *path);
 extern void xstat(char *filename, struct stat *buf);
 extern pid_t spawn(char **argv);
 extern pid_t xspawn(char **argv);

diff --git a/include/usage.h b/include/usage.h
index af518de0be6d86aa7798f9fc8c145f0d438cb4ea..6202c4afd1171b9425f3d9a03f93de47d474d2e9 100644 (file)
--- a/include/usage.h
+++ b/include/usage.h
@@ -3021,7 +3021,8 @@
        "\n     -R HOST[:PORT]  Log to IP or hostname on PORT (default PORT=514/UDP)" \
        "\n     -L      Log locally and via network logging (default is network only)") \
        USE_FEATURE_IPC_SYSLOG( \
-       "\n     -C [size(KiB)]  Log to a circular buffer (read the buffer using logread)")
+       "\n     -C[size(KiB)]   Log to a circular buffer (read the buffer using logread)")
+       /* NB: -Csize shouldn't have space (because size is optional) */
 #define syslogd_example_usage \
        "$ syslogd -R masterlog:514\n" \
        "$ syslogd -R 192.168.1.1:601\n"

diff --git a/libbb/xreadlink.c b/libbb/xreadlink.c
index 14863d9d5f75cae98fdcdcba8235614677eced43..76f52ca060a833006a83f878d8c0b598f7eee8a8 100644 (file)
--- a/libbb/xreadlink.c
+++ b/libbb/xreadlink.c
@@ -4,16 +4,13 @@
  *  Returns a NULL on failure...
  */
 
-#include <stdio.h>
+#include "libbb.h"
 
 /*
  * NOTE: This function returns a malloced char* that you will have to free
  * yourself. You have been warned.
  */
 
-#include <unistd.h>
-#include "libbb.h"
-
 char *xreadlink(const char *path)
 {
        enum { GROWBY = 80 }; /* how large we will grow strings by */
@@ -36,3 +33,16 @@ char *xreadlink(const char *path)
 
        return buf;
 }
+
+char *xmalloc_realpath(const char *path)
+{
+#ifdef __GLIBC__
+       /* glibc provides a non-standard extension */
+       return realpath(path, NULL);
+#else
+       char buf[PATH_MAX+1];
+
+       /* on error returns NULL (xstrdup(NULL) ==NULL) */
+       return xstrdup(realpath(path, buf));
+#endif
+}

diff --git a/sysklogd/logread.c b/sysklogd/logread.c
index 745f97629611789f1e2aed6e0ee26ae349721d9c..4427cf37e9602bf65000b4825eaa6d6c291abd01 100644 (file)
--- a/sysklogd/logread.c
+++ b/sysklogd/logread.c
@@ -9,46 +9,48 @@
  * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
  */
 
-
 #include "busybox.h"
-#include <stdio.h>
-#include <stdlib.h>
-#include <string.h>
 #include <sys/ipc.h>
-#include <sys/types.h>
+//#include <sys/types.h>
 #include <sys/sem.h>
 #include <sys/shm.h>
-#include <signal.h>
-#include <setjmp.h>
-#include <unistd.h>
+//#include <signal.h>
+//#include <setjmp.h>
+
+#define DEBUG 0
 
-static const long KEY_ID = 0x414e4547; /*"GENA"*/
+static const long KEY_ID = 0x414e4547; /* "GENA" */
 
 static struct shbuf_ds {
-       int size;               // size of data written
-       int head;               // start of message list
-       int tail;               // end of message list
+       int32_t size;           // size of data written
+       int32_t head;           // start of message list
+       int32_t tail;           // end of message list
        char data[1];           // data/messages
-} *buf = NULL;                 // shared memory pointer
+} *buf;                                // shared memory pointer
 
 
 // Semaphore operation structures
 static struct sembuf SMrup[1] = {{0, -1, IPC_NOWAIT | SEM_UNDO}}; // set SMrup
 static struct sembuf SMrdn[2] = {{1, 0}, {0, +1, SEM_UNDO}}; // set SMrdn
 
-static int     log_shmid = -1; // ipc shared memory id
-static int     log_semid = -1; // ipc semaphore id
-static jmp_buf jmp_env;
+static int log_shmid = -1;     // ipc shared memory id
+static int log_semid = -1;     // ipc semaphore id
 
-static void error_exit(const char *str);
-static void interrupted(int sig);
+static void error_exit(const char *str) ATTRIBUTE_NORETURN;
+static void error_exit(const char *str)
+{
+       //release all acquired resources
+       if (log_shmid != -1)
+               shmdt(buf);
+       bb_perror_msg_and_die(str);
+}
 
 /*
  * sem_up - up()'s a semaphore.
  */
 static void sem_up(int semid)
 {
-       if ( semop(semid, SMrup, 1) == -1 )
+       if (semop(semid, SMrup, 1) == -1)
                error_exit("semop[SMrup]");
 }
 
@@ -57,52 +59,59 @@ static void sem_up(int semid)
  */
 static void sem_down(int semid)
 {
-       if ( semop(semid, SMrdn, 2) == -1 )
+       if (semop(semid, SMrdn, 2) == -1)
                error_exit("semop[SMrdn]");
 }
 
+static void interrupted(int sig)
+{
+       signal(SIGINT, SIG_IGN);
+       shmdt(buf);
+       exit(0);
+}
+
 int logread_main(int argc, char **argv)
 {
-       int i;
-       int follow=0;
+       int cur;
+       int follow = 1;
 
-       if (argc == 2 && argv[1][0]=='-' && argv[1][1]=='f') {
-               follow = 1;
-       } else {
+       if (argc != 2 || argv[1][0]!='-' || argv[1][1]!='f' ) {
+               follow = 0;
                /* no options, no getopt */
                if (argc > 1)
                        bb_show_usage();
        }
 
-       // handle interrupt signal
-       if (setjmp(jmp_env)) goto output_end;
-
-       // attempt to redefine ^C signal
-       signal(SIGINT, interrupted);
-
-       if ( (log_shmid = shmget(KEY_ID, 0, 0)) == -1)
-               error_exit("Can't find circular buffer");
+       log_shmid = shmget(KEY_ID, 0, 0);
+       if (log_shmid == -1)
+               error_exit("can't find circular buffer");
 
        // Attach shared memory to our char*
-       if ( (buf = shmat(log_shmid, NULL, SHM_RDONLY)) == NULL)
-               error_exit("Can't get access to circular buffer from syslogd");
+       buf = shmat(log_shmid, NULL, SHM_RDONLY);
+       if (buf == NULL)
+               error_exit("can't get access to syslogd buffer");
+
+       log_semid = semget(KEY_ID, 0, 0);
+       if (log_semid == -1)
+               error_exit("can't get access to semaphores for syslogd buffer");
 
-       if ( (log_semid = semget(KEY_ID, 0, 0)) == -1)
-               error_exit("Can't get access to semaphore(s) for circular buffer from syslogd");
+       // attempt to redefine ^C signal
+       signal(SIGINT, interrupted);
 
        // Suppose atomic memory move
-       i = follow ? buf->tail : buf->head;
+       cur = follow ? buf->tail : buf->head;
 
        do {
 #ifdef CONFIG_FEATURE_LOGREAD_REDUCED_LOCKING
                char *buf_data;
-               int log_len,j;
+               int log_len, j;
 #endif
-
                sem_down(log_semid);
 
-               //printf("head: %i tail: %i size: %i\n",buf->head,buf->tail,buf->size);
-               if (buf->head == buf->tail || i==buf->tail) {
+               if (DEBUG)
+                       printf("head:%i cur:%d tail:%i size:%i\n", buf->head, cur, buf->tail, buf->size);
+
+               if (buf->head == buf->tail || cur == buf->tail) {
                        if (follow) {
                                sem_up(log_semid);
                                sleep(1);       /* TODO: replace me with a sleep_on */
@@ -114,58 +123,39 @@ int logread_main(int argc, char **argv)
 
                // Read Memory
 #ifdef CONFIG_FEATURE_LOGREAD_REDUCED_LOCKING
-               log_len = buf->tail - i;
+               log_len = buf->tail - cur;
                if (log_len < 0)
                        log_len += buf->size;
                buf_data = xmalloc(log_len);
 
-               if (buf->tail < i) {
-                       memcpy(buf_data, buf->data+i, buf->size-i);
-                       memcpy(buf_data+buf->size-i, buf->data, buf->tail);
+               if (buf->tail >= cur) {
+                       memcpy(buf_data, buf->data + cur, log_len);
                } else {
-                       memcpy(buf_data, buf->data+i, buf->tail-i);
+                       memcpy(buf_data, buf->data + cur, buf->size - cur);
+                       memcpy(buf_data + buf->size - cur, buf->data, buf->tail);
                }
-               i = buf->tail;
-
+               cur = buf->tail;
 #else
-               while ( i != buf->tail) {
-                       printf("%s", buf->data+i);
-                       i+= strlen(buf->data+i) + 1;
-                       if (i >= buf->size )
-                               i=0;
+               while (cur != buf->tail) {
+                       fputs(buf->data + cur, stdout);
+                       cur += strlen(buf->data + cur) + 1;
+                       if (cur >= buf->size)
+                               cur = 0;
                }
 #endif
                // release the lock on the log chain
                sem_up(log_semid);
 
 #ifdef CONFIG_FEATURE_LOGREAD_REDUCED_LOCKING
-               for (j=0; j < log_len; j+=strlen(buf_data+j)+1) {
-                       printf("%s", buf_data+j);
-                       if (follow)
-                               fflush(stdout);
+               for (j = 0; j < log_len; j += strlen(buf_data+j) + 1) {
+                       fputs(buf_data + j, stdout);
                }
                free(buf_data);
 #endif
                fflush(stdout);
        } while (follow);
 
-output_end:
-       if (log_shmid != -1)
-               shmdt(buf);
+       shmdt(buf);
 
        return EXIT_SUCCESS;
 }
-
-static void interrupted(int sig){
-       signal(SIGINT, SIG_IGN);
-       longjmp(jmp_env, 1);
-}
-
-static void error_exit(const char *str){
-       bb_perror_msg(str);
-       //release all acquired resources
-       if (log_shmid != -1)
-               shmdt(buf);
-
-       exit(1);
-}

diff --git a/sysklogd/syslogd.c b/sysklogd/syslogd.c
index 9e4bc63c2fd66a940828c2ddf82bbec4025a040d..f4644f218d902c69a72cc8c096fa8178ddc441fc 100644 (file)
--- a/sysklogd/syslogd.c
+++ b/sysklogd/syslogd.c
@@ -22,19 +22,14 @@
 #include <sys/syslog.h>
 #include <sys/uio.h>
 
+#define DEBUG 0
+
 /* Path to the unix socket */
-static char dev_log_name[MAXPATHLEN];
+static char *dev_log_name;
 
 /* Path for the file where all log messages are written */
 static const char *logFilePath = "/var/log/messages";
 
-#if ENABLE_FEATURE_ROTATE_LOGFILE
-/* max size of message file before being rotated */
-static int logFileSize = 200 * 1024;
-/* number of rotated message files */
-static int logFileRotate = 1;
-#endif
-
 /* interval between marks in seconds */
 static int markInterval = 20 * 60;
 
@@ -44,6 +39,13 @@ static int logLevel = 8;
 /* localhost's name */
 static char localHostName[64];
 
+#if ENABLE_FEATURE_ROTATE_LOGFILE
+/* max size of message file before being rotated */
+static int logFileSize = 200 * 1024;
+/* number of rotated message files */
+static int logFileRotate = 1;
+#endif
+
 #if ENABLE_FEATURE_REMOTE_LOG
 #include <netinet/in.h>
 /* udp socket for logging to remote host */
@@ -142,6 +144,9 @@ static void ipcsyslog_cleanup(void)
 
 static void ipcsyslog_init(void)
 {
+       if (DEBUG)
+               printf("shmget(%lx, %d,...)\n", KEY_ID, shm_size);
+
        shmid = shmget(KEY_ID, shm_size, IPC_CREAT | 1023);
        if (shmid == -1) {
                bb_perror_msg_and_die("shmget");
@@ -236,6 +241,8 @@ static void log_to_shmem(const char *msg, int len)
        if (semop(s_semid, SMwup, 1) == -1) {
                bb_perror_msg_and_die("SMwup");
        }
+       if (DEBUG)
+               printf("head:%d tail:%d\n", shbuf->head, shbuf->tail);
 }
 #else
 void ipcsyslog_cleanup(void);
@@ -450,10 +457,12 @@ static void do_syslogd(void)
        signal(SIGALRM, do_mark);
        alarm(markInterval);
 
+       dev_log_name = xmalloc_realpath(_PATH_LOG);
+       if (!dev_log_name)
+               dev_log_name = _PATH_LOG;
+
        /* Unlink old /dev/log (or object it points to) */
-       if (realpath(_PATH_LOG, dev_log_name) != NULL) {
-               unlink(dev_log_name);
-       }
+       unlink(dev_log_name);
 
        memset(&sunx, 0, sizeof(sunx));
        sunx.sun_family = AF_UNIX;
@@ -520,6 +529,7 @@ int syslogd_main(int argc, char **argv)
        char *p;
 
        /* do normal option parsing */
+       opt_complementary = "=0"; /* no non-option params */
        getopt32(argc, argv, OPTION_STR, OPTION_PARAM);
        if (option_mask32 & OPT_mark) // -m
                markInterval = xatou_range(opt_m, 0, INT_MAX/60) * 60;