syslogd: fix it for small BUFSIZ case

1 files changed, 67 insertions, 71 deletions

diff --git a/sysklogd/syslogd.c b/sysklogd/syslogd.c
index 8ae75c974..2a2b20c8b 100644
--- a/sysklogd/syslogd.c
+++ b/sysklogd/syslogd.c
@@ -37,61 +37,75 @@
 
 #define DEBUG 0
 
-// Semaphore operation structures
-struct shbuf_ds {
-        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
-};                      // shared memory pointer
-
-struct globals {
-
-        const char *logFilePath;
-        int logFD;
-
-        /* This is not very useful, is bloat, and broken:
-         * can deadlock if alarmed to make MARK while writing to IPC buffer
-         * (semaphores are down but do_mark routine tries to down them again) */
-#ifdef SYSLOGD_MARK
-        /* interval between marks in seconds */
-        int markInterval;
-#endif
+/* MARK code is not very useful, is bloat, and broken:
+ * can deadlock if alarmed to make MARK while writing to IPC buffer
+ * (semaphores are down but do_mark routine tries to down them again) */
+#undef SYSLOGD_MARK
 
-        /* level of messages to be locally logged */
-        int logLevel;
+enum { MAX_READ = 256 };
 
-#if ENABLE_FEATURE_ROTATE_LOGFILE
-        /* max size of message file before being rotated */
-        unsigned logFileSize;
-        /* number of rotated message files */
-        unsigned logFileRotate;
-        unsigned curFileSize;
-        smallint isRegular;
-#endif
+/* Semaphore operation structures */
+struct shbuf_ds {
+        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 */
+};
 
-#if ENABLE_FEATURE_REMOTE_LOG
-        /* udp socket for logging to remote host */
-        int remoteFD;
-        len_and_sockaddr* remoteAddr;
-#endif
+/* Allows us to have smaller initializer. Ugly. */
+#define GLOBALS \
+        const char *logFilePath;                \
+        int logFD;                              \
+        /* interval between marks in seconds */ \
+        /*int markInterval;*/                   \
+        /* level of messages to be logged */    \
+        int logLevel;                           \
+USE_FEATURE_ROTATE_LOGFILE( \
+        /* max size of file before rotation */  \
+        unsigned logFileSize;                   \
+        /* number of rotated message files */   \
+        unsigned logFileRotate;                 \
+        unsigned curFileSize;                   \
+        smallint isRegular;                     \
+) \
+USE_FEATURE_REMOTE_LOG( \
+        /* udp socket for remote logging */     \
+        int remoteFD;                           \
+        len_and_sockaddr* remoteAddr;           \
+) \
+USE_FEATURE_IPC_SYSLOG( \
+        int shmid; /* ipc shared memory id */   \
+        int s_semid; /* ipc semaphore id */     \
+        int shm_size;                           \
+        struct sembuf SMwup[1];                 \
+        struct sembuf SMwdn[3];                 \
+)
+
+struct init_globals {
+        GLOBALS
+};
 
+struct globals {
+        GLOBALS
 #if ENABLE_FEATURE_IPC_SYSLOG
-        int shmid; // ipc shared memory id
-        int s_semid; // ipc semaphore id
-        int shm_size;
-        struct sembuf SMwup[1];
-        struct sembuf SMwdn[3];
         struct shbuf_ds *shbuf;
 #endif
-
         time_t last_log_time;
         /* localhost's name */
         char localHostName[64];
 
-}; /* struct globals */
+        /* We recv into recvbuf... */
+        char recvbuf[MAX_READ];
+        /* ...then copy to parsebuf, escaping control chars */
+        /* (can grow x2 max) */
+        char parsebuf[MAX_READ*2];
+        /* ...then sprintf into printbuf, adding timestamp (15 chars),
+         * host (64), fac.prio (20) to the message */
+        /* (growth by: 15 + 64 + 20 + delims = ~110) */
+        char printbuf[MAX_READ*2 + 128];
+};
 
-static const struct globals init_globals = {
+static const struct init_globals init_data = {
         .logFilePath = "/var/log/messages",
         .logFD = -1,
 #ifdef SYSLOGD_MARK
@@ -112,28 +126,11 @@ static const struct globals init_globals = {
         .SMwup = { {1, -1, IPC_NOWAIT} },
         .SMwdn = { {0, 0}, {1, 0}, {1, +1} },
 #endif
-        // FIXME: hidden tail with lotsa zeroes is here....
 };
 
 #define G (*ptr_to_globals)
 
 
-/* We are using bb_common_bufsiz1 for buffering: */
-enum { MAX_READ = (BUFSIZ/6) & ~0xf };
-/* We recv into RECVBUF... (size: MAX_READ ~== BUFSIZ/6) */
-#define RECVBUF  bb_common_bufsiz1
-/* ...then copy to PARSEBUF, escaping control chars */
-/* (can grow x2 max ~== BUFSIZ/3) */
-#define PARSEBUF (bb_common_bufsiz1 + MAX_READ)
-/* ...then sprintf into PRINTBUF, adding timestamp (15 chars),
- * host (64), fac.prio (20) to the message */
-/* (growth by: 15 + 64 + 20 + delims = ~110) */
-#define PRINTBUF (bb_common_bufsiz1 + 3*MAX_READ)
-/* totals: BUFSIZ == BUFSIZ/6 + BUFSIZ/3 + (BUFSIZ/3+BUFSIZ/6)
- * -- we have BUFSIZ/6 extra at the ent of PRINTBUF
- * which covers needed ~110 extra bytes (and much more) */
-
-
 /* Options */
 enum {
         OPTBIT_mark = 0, // -m
@@ -437,13 +434,13 @@ static void timestamp_and_log(int pri, char *msg, int len)
         if (!ENABLE_FEATURE_REMOTE_LOG || (option_mask32 & OPT_locallog)) {
                 if (LOG_PRI(pri) < G.logLevel) {
                         if (option_mask32 & OPT_small)
-                                sprintf(PRINTBUF, "%s %s\n", timestamp, msg);
+                                sprintf(G.printbuf, "%s %s\n", timestamp, msg);
                         else {
                                 char res[20];
                                 parse_fac_prio_20(pri, res);
-                                sprintf(PRINTBUF, "%s %s %s %s\n", timestamp, G.localHostName, res, msg);
+                                sprintf(G.printbuf, "%s %s %s %s\n", timestamp, G.localHostName, res, msg);
                         }
-                        log_locally(PRINTBUF);
+                        log_locally(G.printbuf);
                 }
         }
 }
@@ -455,7 +452,7 @@ static void split_escape_and_log(char *tmpbuf, int len)
         tmpbuf += len;
         while (p < tmpbuf) {
                 char c;
-                char *q = PARSEBUF;
+                char *q = G.parsebuf;
                 int pri = (LOG_USER | LOG_NOTICE);
 
                 if (*p == '<') {
@@ -478,7 +475,7 @@ static void split_escape_and_log(char *tmpbuf, int len)
                 }
                 *q = '\0';
                 /* Now log it */
-                timestamp_and_log(pri, PARSEBUF, q - PARSEBUF);
+                timestamp_and_log(pri, G.parsebuf, q - G.parsebuf);
         }
 }
 
@@ -572,7 +569,7 @@ static void do_syslogd(void)
 
                 if (FD_ISSET(sock_fd, &fds)) {
                         int i;
-                        i = recv(sock_fd, RECVBUF, MAX_READ - 1, 0);
+                        i = recv(sock_fd, G.recvbuf, MAX_READ - 1, 0);
                         if (i <= 0)
                                 bb_perror_msg_and_die("UNIX socket error");
                         /* TODO: maybe suppress duplicates? */
@@ -585,13 +582,13 @@ static void do_syslogd(void)
                                 }
                                 if (-1 != G.remoteFD) {
                                         /* send message to remote logger, ignore possible error */
-                                        sendto(G.remoteFD, RECVBUF, i, MSG_DONTWAIT,
+                                        sendto(G.remoteFD, G.recvbuf, i, MSG_DONTWAIT,
                                                 &G.remoteAddr->sa, G.remoteAddr->len);
                                 }
                         }
 #endif
-                        RECVBUF[i] = '\0';
-                        split_escape_and_log(RECVBUF, i);
+                        G.recvbuf[i] = '\0';
+                        split_escape_and_log(G.recvbuf, i);
                 } /* FD_ISSET() */
         } /* for */
 }
@@ -602,8 +599,7 @@ int syslogd_main(int argc, char **argv)
         char OPTION_DECL;
         char *p;
 
-        PTR_TO_GLOBALS = xzalloc(sizeof(G));
-        memcpy(ptr_to_globals, &init_globals, sizeof(init_globals));
+        PTR_TO_GLOBALS = memcpy(xzalloc(sizeof(G)), &init_data, sizeof(init_data));
 
         /* do normal option parsing */
         opt_complementary = "=0"; /* no non-option params */