commit 4223e80d23375c49b0e3ae636c6217c3d1aad9c6
parent b68ac836fc9ac562494f74c2c7186025b5102b5b
Author: leitner <leitner>
Date: Thu, 25 Sep 2014 15:29:04 +0000
add ftrigger (run a command if a file changes)
Diffstat:
| M | CHANGES | | | 1 | + |
| M | Makefile | | | 5 | +++-- |
| A | ftrigger.c | | | 200 | +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++ |
3 files changed, 204 insertions(+), 2 deletions(-)
diff --git a/CHANGES b/CHANGES
@@ -9,6 +9,7 @@
started
only install SIGWINCH and SIGINT if running with PID 1
you can now do "make MINITROOT=/var/minit"
+ add ftrigger (run a command if a file changes)
0.10:
add sample script for /etc/minit/ctrlaltdel/run as
diff --git a/Makefile b/Makefile
@@ -1,5 +1,5 @@
all: minit msvc pidfilehack hard-reboot write_proc killall5 shutdown \
-minit-update serdo
+minit-update serdo ftrigger
#CFLAGS=-pipe -march=i386 -fomit-frame-pointer -Os -I../dietlibc/include
CC=gcc
@@ -48,6 +48,7 @@ endif
minit: minit.o split.o openreadclose.o opendevconsole.o
msvc: msvc.o
+ftrigger: ftrigger.o
minit-update: minit-update.o split.o openreadclose.o
serdo: serdo.o
@@ -62,7 +63,7 @@ shutdown: shutdown.o split.o openreadclose.o opendevconsole.o
clean:
rm -f *.o minit msvc pidfilehack hard-reboot write_proc killall5 \
- shutdown minit-update serdo
+ shutdown minit-update serdo ftrigger
test: test.c
gcc -nostdlib -o $@ $^ -I../dietlibc/include ../dietlibc/start.o ../dietlibc/dietlibc.a
diff --git a/ftrigger.c b/ftrigger.c
@@ -0,0 +1,200 @@
+#include <sys/types.h>
+#include <unistd.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+#include <sys/inotify.h>
+#include <stdlib.h>
+#include <string.h>
+#include <buffer.h>
+#include <errno.h>
+#include <sys/poll.h>
+#include <sys/wait.h>
+#include <sys/signal.h>
+
+struct trigger {
+ const char* filename,* command;
+ char* dironly,* fileonly;
+ struct stat ss;
+ int idd,idf; /* inotify-deskriptor */
+}* root;
+int n;
+
+void sighandler(int signum) {
+ int status;
+ (void)signum;
+ wait(&status);
+}
+
+int main(int argc,char* argv[]) {
+ int i,in,v=0;
+ const char* command="make";
+ struct stat ss;
+ char buf[2048];
+ struct inotify_event* ie=(struct inotify_event*)buf;
+ struct pollfd p;
+ static struct sigaction sa;
+
+ sa.sa_flags=SA_RESTART|SA_NOCLDSTOP;
+ sa.sa_handler=SIG_IGN;
+ sigaction(SIGCHLD,&sa,0);
+ in=inotify_init();
+ root=(struct trigger*)alloca(sizeof(struct trigger)*argc);
+ memset(root,0,sizeof(struct trigger)*argc);
+ for (i=1; i<argc; ++i) {
+ if (!strcmp(argv[i],"-v")) {
+ v=1;
+ continue;
+ }
+ if (argv[i][0]=='@') {
+ command=argv[i]+1;
+ ++i;
+ }
+ if (argv[i]) {
+ char* c;
+ root[n].filename=argv[i];
+ root[n].command=command;
+ root[n].dironly=alloca(strlen(root[n].filename)+3);
+ c=strrchr(root[n].filename,'/');
+ if (c) {
+ size_t m=c-root[n].filename;
+ strcpy(root[n].dironly,root[n].filename);
+ root[n].fileonly=root[n].dironly+m+1;
+ *c=0;
+ } else {
+ root[n].dironly[0]='.';
+ root[n].dironly[1]=0;
+ root[n].fileonly=root[n].dironly+2;
+ strcpy(root[n].fileonly,root[n].filename);
+ }
+ ++n;
+ }
+ }
+
+ for (i=0; i<n; ++i) {
+ root[i].idf=-1;
+ if (stat(root[i].filename,&root[i].ss)!=0)
+ buffer_putmflush(buffer_2,"warning: could not stat file \"",root[i].filename,"\": ",strerror(errno),"\n");
+ else
+ root[i].idf=inotify_add_watch(in,root[i].filename,
+ IN_CLOSE_WRITE|IN_MOVE_SELF|IN_DELETE_SELF);
+ root[i].idd=inotify_add_watch(in,root[i].dironly,
+ IN_MOVED_TO|IN_CREATE);
+ }
+
+ p.fd=in;
+ p.events=POLLIN;
+
+ for (;;) {
+again:
+ switch (poll(&p,1,1000)) {
+ case -1:
+ if (errno==EINTR) {
+ int status;
+ wait(&status);
+ break;
+ }
+ return 1;
+ case 0: continue;
+ case 1: break;
+ };
+ read(in,buf,sizeof(buf));
+
+#if 0
+ buffer_puts(buffer_1,"got event for wd ");
+ buffer_putulong(buffer_1,ie->wd);
+ if (ie->len)
+ buffer_putmflush(buffer_1," with filename \"",ie->name,"\"\n");
+ else
+ buffer_putsflush(buffer_1," with no associated filename\n");
+ struct {
+ unsigned int mask;
+ const char* string;
+ } strings[] = {
+ { 0x00000001,"IN_ACCESS" },
+ { 0x00000002,"IN_MODIFY" },
+ { 0x00000004,"IN_ATTRIB" },
+ { 0x00000008,"IN_CLOSE_WRITE" },
+ { 0x00000010,"IN_CLOSE_NOWRITE" },
+ { 0x00000020,"IN_OPEN" },
+ { 0x00000040,"IN_MOVED_FROM" },
+ { 0x00000080,"IN_MOVED_TO" },
+ { 0x00000100,"IN_CREATE" },
+ { 0x00000200,"IN_DELETE" },
+ { 0x00000400,"IN_DELETE_SELF" },
+ { 0x00000800,"IN_MOVE_SELF" },
+ { 0x00002000,"IN_UNMOUNT" },
+ { 0x00004000,"IN_Q_OVERFLOW" },
+ { 0x00008000,"IN_IGNORED" },
+ };
+
+ for (i=0; i<(int)(sizeof(strings)/sizeof(strings[0])); ++i) {
+ if (ie->mask&strings[i].mask)
+ buffer_putm(buffer_1," ",strings[i].string);
+ }
+ buffer_putnlflush(buffer_1);
+
+#endif
+
+ for (i=0; i<n; ++i) {
+ if (root[i].idf==ie->wd) {
+ if (ie->mask & (IN_DELETE_SELF|IN_MOVE_SELF)) {
+#if 0
+ buffer_putmflush(buffer_1,root[i].filename," was ",
+ ie->mask&IN_DELETE_SELF ? "deleted" : "renamed",
+ ", cancelling subscription\n");
+#endif
+ inotify_rm_watch(in,ie->wd);
+ root[i].idf=-1;
+ goto again;
+ }
+ goto goodevent;
+ } else if (root[i].idd==ie->wd) {
+ if (!strcmp(ie->name,root[i].fileonly)) {
+#if 0
+ buffer_putmflush(buffer_1,"the file we were interested in, ",
+ root[i].filename,", has been created. Adding subscription.\n");
+#endif
+ if (root[i].idf!=-1)
+ inotify_rm_watch(in,root[i].idf);
+ root[i].idf=inotify_add_watch(in,root[i].filename,
+ IN_CLOSE_WRITE|IN_MOVE_SELF|IN_DELETE_SELF);
+ /* if the file was created, it will be empty now, wait for
+ * the IN_CLOSE_WRITE event. */
+ if (ie->mask & IN_CREATE) {
+#if 0
+ buffer_putmflush(buffer_1,"file was created, so it will be empty now. Skipping until we get a close event.\n");
+#endif
+ goto again;
+ }
+ goto goodevent;
+ /* if the file was moved, this is a genuine event we are
+ * interested in. fall through */
+ } else goto again;
+#if 0
+ buffer_putmflush(buffer_1,"(directory event for \"",root[i].filename,"\")\n");
+#endif
+ }
+ }
+#if 0
+ buffer_putmflush(buffer_1,"ignoring irrelevant event.\n");
+#endif
+ goto again;
+
+goodevent:
+#if 0
+ buffer_putmflush(buffer_1,"got through to stat\n");
+#endif
+ for (i=0; i<n; ++i) {
+ if (stat(root[i].filename,&ss)==0 && memcmp(&ss,&root[i].ss,sizeof(ss))) {
+ memcpy(&root[i].ss,&ss,sizeof(ss));
+ if (v)
+ buffer_putmflush(buffer_1,"file \"",root[i].filename,"\" changed, running command \"",root[i].command,"\"\n");
+ if (vfork()==0) {
+ system(root[i].command);
+ exit(0);
+ }
+ }
+ }
+ }
+ return 0;
+}
