summaryrefslogtreecommitdiff
path: root/src/minutils
diff options
context:
space:
mode:
Diffstat (limited to 'src/minutils')
-rw-r--r--src/minutils/s6-logwatch.c204
1 files changed, 109 insertions, 95 deletions
diff --git a/src/minutils/s6-logwatch.c b/src/minutils/s6-logwatch.c
index 42214d7..6100cbd 100644
--- a/src/minutils/s6-logwatch.c
+++ b/src/minutils/s6-logwatch.c
@@ -2,69 +2,112 @@
#include <sys/uio.h>
#include <errno.h>
+#include <limits.h>
#include <string.h>
#include <unistd.h>
#include <signal.h>
-#include <sys/ioctl.h>
#include <sys/inotify.h>
+#include <skalibs/types.h>
#include <skalibs/allreadwrite.h>
#include <skalibs/sgetopt.h>
#include <skalibs/strerr2.h>
#include <skalibs/error.h>
#include <skalibs/buffer.h>
-#include <skalibs/bufalloc.h>
#include <skalibs/sig.h>
#include <skalibs/djbunix.h>
#include <skalibs/iopause.h>
-#include <skalibs/types.h>
-#define USAGE "s6-logwatch [ -m maxbuffer ] logdir"
+#define USAGE "s6-logwatch [ logdir ]"
#define dieusage() strerr_dieusage(100, USAGE)
-#define N 4096
-#define IESIZE 100
+#define B_READING 0
+#define B_BLOCKING 1
+#define B_WAITING 2
+static unsigned int state ;
+static int fd ;
+static int newcurrent = 0 ;
-typedef enum bstate_e bstate_t, *bstate_t_ref ;
-enum bstate_e
+union inotify_event_u
{
- B_TAILING = 0,
- B_WAITING = 1
+ struct inotify_event event ;
+ char buf[sizeof(struct inotify_event) + NAME_MAX + 1] ;
} ;
-static void X (void)
+static void goteof (void)
{
- strerr_diefu1x(101, "follow file state changes (race condition triggered). Sorry.") ;
+ if (newcurrent)
+ {
+ fd_close(fd) ;
+ fd = open_read("current") ;
+ if (fd < 0) strerr_diefu1sys(111, "current") ;
+ newcurrent = 0 ;
+ state = B_READING ;
+ }
+ else state = B_BLOCKING ;
}
-static size_t nbcat (int fdcurrent)
+static int readit (int fd)
{
- char buf[N+1] ;
- buffer b = BUFFER_INIT(&fd_readv, fdcurrent, buf, N+1) ;
struct iovec v[2] ;
- size_t bytes = 0 ;
- for (;;)
+ ssize_t r ;
+ buffer_wpeek(buffer_1, v) ;
+ r = fd_readv(fd, v, 2) ;
+ switch (r)
+ {
+ case -1 : return 0 ;
+ case 0 : goteof() ; break ;
+ default : buffer_wseek(buffer_1, r) ;
+ }
+ return 1 ;
+}
+
+static void maketransition (unsigned int transition)
+{
+ static unsigned char const table[3][3] = {
+ { 0x10, 0x00, 0x00 },
+ { 0x60, 0x22, 0x00 },
+ { 0x40, 0x03, 0x02 }
+ } ;
+ unsigned char c = table[state][transition] ;
+ state = c & 0x0f ;
+ if (state == 3) strerr_dief1x(101, "current moved twice without being recreated") ;
+ if (c & 0x10) newcurrent = 1 ;
+ if (c & 0x20) { fd_close(fd) ; fd = -1 ; }
+ if (c & 0x40)
{
- ssize_t r = sanitize_read(buffer_fill(&b)) ;
- if (!r) break ;
- if (r < 0)
+ fd = open_read("current") ;
+ if (fd < 0) strerr_diefu1sys(111, "current") ;
+ }
+}
+
+static void handle_event (int ifd, int watch)
+{
+ ssize_t r ;
+ size_t offset = 0 ;
+ union inotify_event_u u ;
+ r = read(ifd, u.buf, sizeof(u.buf)) ;
+ while (r > 0)
+ {
+ struct inotify_event *event = (struct inotify_event *)(u.buf + offset) ;
+ offset += sizeof(struct inotify_event) + event->len ;
+ r -= sizeof(struct inotify_event) + event->len ;
+ if (event->wd == watch && !strcmp(event->name, "current"))
{
- if (errno == EPIPE) break ;
- else strerr_diefu1sys(111, "buffer_fill") ;
+ int transition = -1 ;
+ if (event->mask & IN_CREATE) transition = 0 ;
+ else if (event->mask & IN_MOVED_FROM) transition = 1 ;
+ else if (event->mask & IN_MODIFY) transition = 2 ;
+ if (transition >= 0) maketransition(transition) ;
}
- buffer_rpeek(&b, v) ;
- if (!bufalloc_putv(bufalloc_1, v, 2))
- strerr_diefu1sys(111, "bufalloc_putv") ;
- buffer_rseek(&b, r) ;
- bytes += r ;
}
- return bytes ;
}
-
int main (int argc, char const *const *argv)
{
+ iopause_fd x[2] = { { .events = IOPAUSE_READ }, { .fd = 1 } } ;
char const *dir = "." ;
- unsigned long maxlen = 4000 ;
+ int watch ;
+ unsigned int maxlen = 4096 ;
PROG = "s6-logwatch" ;
{
subgetopt_t l = SUBGETOPT_ZERO ;
@@ -74,7 +117,10 @@ int main (int argc, char const *const *argv)
if (opt == -1) break ;
switch (opt)
{
- case 'm' : if (!ulong0_scan(l.arg, &maxlen)) dieusage() ; break ;
+ case 'm' :
+ if (!uint0_scan(l.arg, &maxlen)) dieusage() ;
+ strerr_warnw1x("the -m option is deprecated") ;
+ break ;
default : dieusage() ;
}
}
@@ -83,74 +129,42 @@ int main (int argc, char const *const *argv)
if (argc) dir = *argv ;
if (chdir(dir) < 0) strerr_diefu2sys(111, "chdir to ", dir) ;
+
+ x[0].fd = inotify_init1(IN_NONBLOCK | IN_CLOEXEC) ;
+ if (x[0].fd < 0) strerr_diefu1sys(111, "inotify_init") ;
+ watch = inotify_add_watch(x[0].fd, ".", IN_CREATE | IN_MOVED_FROM | IN_MODIFY) ;
+ if (watch < 0) strerr_diefu1sys(111, "inotify_add_watch") ;
+ fd = open_readb("current") ;
+ if (fd < 0)
{
- iopause_fd x[1] = { { -1, IOPAUSE_READ, 0 } } ;
- size_t pos = 0 ;
- int fdcurrent = -1 ;
- int w ;
- bstate_t state = B_TAILING ;
- x[0].fd = inotify_init() ;
- if (x[0].fd < 0) strerr_diefu1sys(111, "inotify_init") ;
- if (ndelay_on(x[0].fd) < 0) strerr_diefu1sys(111, "ndelay_on inotify fd") ;
- w = inotify_add_watch(x[0].fd, ".", IN_CREATE | IN_MODIFY | IN_CLOSE_WRITE) ;
- if (w < 0) strerr_diefu1sys(111, "inotify_add_watch") ;
- if (sig_ignore(SIGPIPE) == -1) strerr_diefu1sys(111, "sig_ignore(SIGPIPE)") ;
- fdcurrent = open_readb("current") ;
- if (fdcurrent < 0)
- if (errno != ENOENT) strerr_diefu1sys(111, "open_readb current") ;
- else state = B_WAITING ;
- else pos = nbcat(fdcurrent) ;
+ if (errno != ENOENT) strerr_diefu3sys(111, "open ", dir, "/current") ;
+ state = B_WAITING ;
+ }
+ else state = B_READING ;
+ if (sig_ignore(SIGPIPE) == -1) strerr_diefu1sys(111, "sig_ignore(SIGPIPE)") ;
+ if (state == B_READING)
+ {
+ if (!readit(fd)) strerr_diefu3sys(111, "read from ", dir, "/current") ;
+ }
- for (;;)
+ for (;;)
+ {
+ int r ;
+ x[1].events = buffer_len(buffer_1) ? IOPAUSE_WRITE : 0 ;
+ r = iopause(x, 2, 0, 0) ;
+ if (r < 0) strerr_diefu1sys(111, "iopause") ;
+ if (x[0].revents & IOPAUSE_EXCEPT) x[0].revents |= IOPAUSE_READ ;
+ if (x[1].revents & IOPAUSE_EXCEPT) x[1].revents |= IOPAUSE_WRITE ;
+ if (x[1].revents & IOPAUSE_WRITE)
{
- int rr ;
- if (!bufalloc_flush(bufalloc_1)) strerr_diefu1sys(111, "write to stdout") ;
- rr = iopause(x, 1, 0, 0) ;
- if (rr < 0) strerr_diefu1sys(111, "iopause") ;
- if (x[0].revents & IOPAUSE_READ)
- {
- char iebuf[IESIZE] ;
- while (bufalloc_len(bufalloc_1) < maxlen)
- {
- size_t i = 0 ;
- ssize_t r = sanitize_read(fd_read(x[0].fd, iebuf, IESIZE)) ;
- if (r < 0) strerr_diefu1sys(111, "read from inotify fd") ;
- if (!r) break ;
- while (i < (size_t)r)
- {
- struct inotify_event *ie = (struct inotify_event *)(iebuf + i) ;
- if ((ie->wd != w) || !ie->len || strcmp(ie->name, "current")) goto cont ;
- if (ie->mask & IN_MODIFY)
- {
- if (state) X() ;
- pos += nbcat(fdcurrent) ;
- }
- else if (ie->mask & IN_CLOSE_WRITE)
- {
- if (state) X() ;
- fd_close(fdcurrent) ;
- fdcurrent = -1 ;
- pos = 0 ;
- state = B_WAITING ;
- }
- else if (ie->mask & IN_CREATE)
- {
- if (!state) X() ;
- fdcurrent = open_readb("current") ;
- if (fdcurrent < 0)
- {
- if (errno != ENOENT) strerr_diefu1sys(111, "open_readb current") ;
- else goto cont ;
- }
- pos = nbcat(fdcurrent) ;
- state = B_TAILING ;
- }
- cont:
- i += sizeof(struct inotify_event) + ie->len ;
- }
- }
- }
+ if (!buffer_flush(buffer_1) && !error_isagain(errno))
+ strerr_diefu1sys(111, "write to stdout") ;
+ }
+ if (state == B_READING && buffer_available(buffer_1))
+ {
+ if (!readit(fd)) strerr_diefu3sys(111, "read from ", dir, "/current") ;
}
+ if (x[0].revents & IOPAUSE_READ) handle_event(x[0].fd, watch) ;
}
return 0 ;
}
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-14 05:48:30 +0000