X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ian/git?p=secnet.git;a=blobdiff_plain;f=util.c;h=d843859f40dcb5fe6593592547888c98b63bbda2;hp=7d102b129afd2d33bee3536f678859fdf59d3c00;hb=b85fe3f90b025a3742bf1c0ea91bc213a421f74d;hpb=f54d5adadd831fd0fa55d70d3aaffe60636818f5

diff --git a/util.c b/util.c
index 7d102b1..d843859 100644
--- a/util.c
+++ b/util.c
@@ -53,10 +53,10 @@ uint32_t current_phase=0;
 struct phase_hook {
     hook_fn *fn;
     void *state;
-    struct phase_hook *next;
+    LIST_ENTRY(phase_hook) entry;
 };
 
-static struct phase_hook *hooks[NR_PHASES]={NULL,};
+static LIST_HEAD(, phase_hook) hooks[NR_PHASES];
 
 char *safe_strdup(const char *s, const char *message)
 {
@@ -204,22 +204,38 @@ static const char *phases[NR_PHASES]={
     "PHASE_GETRESOURCES",
     "PHASE_DROPPRIV",
     "PHASE_RUN",
-    "PHASE_SHUTDOWN"
+    "PHASE_SHUTDOWN",
+    "PHASE_CHILDPERSIST"
 };
 
 void enter_phase(uint32_t new_phase)
 {
     struct phase_hook *i;
 
-    if (hooks[new_phase])
+    if (!LIST_EMPTY(&hooks[new_phase]))
 	Message(M_DEBUG_PHASE,"Running hooks for %s...\n", phases[new_phase]);
     current_phase=new_phase;
 
-    for (i=hooks[new_phase]; i; i=i->next)
+    LIST_FOREACH(i, &hooks[new_phase], entry)
 	i->fn(i->state, new_phase);
     Message(M_DEBUG_PHASE,"Now in %s\n",phases[new_phase]);
 }
 
+void phase_hooks_init(void)
+{
+    int i;
+    for (i=0; i<NR_PHASES; i++)
+	LIST_INIT(&hooks[i]);
+}
+
+void clear_phase_hooks(uint32_t phase)
+{
+    struct phase_hook *h, *htmp;
+    LIST_FOREACH_SAFE(h, &hooks[phase], entry, htmp)
+	free(h);
+    LIST_INIT(&hooks[phase]);
+}
+
 bool_t add_hook(uint32_t phase, hook_fn *fn, void *state)
 {
     struct phase_hook *h;
@@ -227,8 +243,7 @@ bool_t add_hook(uint32_t phase, hook_fn *fn, void *state)
     h=safe_malloc(sizeof(*h),"add_hook");
     h->fn=fn;
     h->state=state;
-    h->next=hooks[phase];
-    hooks[phase]=h;
+    LIST_INSERT_HEAD(&hooks[phase],h,entry);
     return True;
 }
 
@@ -285,6 +300,14 @@ void buffer_init(struct buffer_if *buffer, int32_t max_start_pad)
     buffer->size=0;
 }
 
+void buffer_destroy(struct buffer_if *buf)
+{
+    BUF_ASSERT_FREE(buf);
+    free(buf->base);
+    buf->start=buf->base=0;
+    buf->size=buf->alloclen=0;
+}
+
 void *buf_append(struct buffer_if *buf, int32_t amount) {
     void *p;
     assert(amount <= buf_remaining_space(buf));
@@ -598,3 +621,97 @@ int iaddr_socklen(const union iaddr *ia)
     default:       abort();
     }
 }
+
+const char *pollbadbit(int revents)
+{
+#define BADBIT(b) \
+    if ((revents & b)) return #b
+    BADBIT(POLLERR);
+    BADBIT(POLLHUP);
+    /* POLLNVAL is handled by the event loop - see afterpoll_fn comment */
+#undef BADBIT
+    return 0;
+}
+
+enum async_linebuf_result
+async_linebuf_read(struct pollfd *pfd, struct buffer_if *buf,
+		   const char **emsg_out)
+{
+    int revents=pfd->revents;
+
+#define BAD(m) do{ *emsg_out=(m); return async_linebuf_broken; }while(0)
+
+    const char *badbit=pollbadbit(revents);
+    if (badbit) BAD(badbit);
+
+    if (!(revents & POLLIN))
+	return async_linebuf_nothing;
+
+    /*
+     * Data structure: A line which has been returned to the user is
+     * stored in buf at base before start.  But we retain the usual
+     * buffer meaning of size.  So:
+     *
+     *   | returned :    | input read,   |    unused    |
+     *   |  to user : \0 |  awaiting     |     buffer   |
+     *   |          :    |  processing   |      space   |
+     *   |          :    |               |              |
+     *   ^base           ^start          ^start+size    ^base+alloclen
+     */
+
+    BUF_ASSERT_USED(buf);
+
+    /* firstly, eat any previous */
+    if (buf->start != buf->base) {
+	memmove(buf->base,buf->start,buf->size);
+	buf->start=buf->base;
+    }
+
+    uint8_t *searched=buf->base;
+
+    /*
+     * During the workings here we do not use start.  We set start
+     * when we return some actual data.  So we have this:
+     *
+     *   | searched     | read, might   |  unused      |
+     *   |  for \n      |  contain \n   |   buffer     |
+     *   |  none found  |  but not \0   |    space     |
+     *   |              |               |              |
+     *   ^base          ^searched       ^base+size     ^base+alloclen
+     *  [^start]                        ^dataend
+     *
+     */
+    for (;;) {
+	uint8_t *dataend=buf->base+buf->size;
+	char *newline=memchr(searched,'\n',dataend-searched);
+	if (newline) {
+	    *newline=0;
+	    buf->start=newline+1;
+	    buf->size=dataend-buf->start;
+	    return async_linebuf_ok;
+	}
+	searched=dataend;
+	ssize_t space=(buf->base+buf->alloclen)-dataend;
+	if (!space) BAD("input line too long");
+	ssize_t r=read(pfd->fd,searched,space);
+	if (r==0) {
+	    *searched=0;
+	    *emsg_out=buf->size?"no newline at eof":0;
+	    buf->start=searched+1;
+	    buf->size=0;
+	    return async_linebuf_eof;
+	}
+	if (r<0) {
+	    if (errno==EINTR)
+		continue;
+	    if (iswouldblock(errno))
+		return async_linebuf_nothing;
+	    BAD(strerror(errno));
+	}
+	assert(r<=space);
+	if (memchr(searched,0,r)) BAD("nul in input data");
+	buf->size+=r;
+    }
+
+#undef BAD
+}