X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=util.c;h=0215f257620b29955da29135aa332cf044bcf944;hb=46d06c3918b0080af7e87db986612e23bde4a341;hp=9c8abb3393353cf08322d4292f9e0e4d0c71ccfd;hpb=bb8398990f4b904047ddd8543f24c4ae683e1881;p=secnet.git

diff --git a/util.c b/util.c
index 9c8abb3..0215f25 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)
 {
@@ -71,17 +71,30 @@ char *safe_strdup(const char *s, const char *message)
 void *safe_malloc(size_t size, const char *message)
 {
     void *r;
+    if (!size)
+	return 0;
     r=malloc(size);
     if (!r) {
 	fatal_perror("%s",message);
     }
     return r;
 }
-void *safe_malloc_ary(size_t size, size_t count, const char *message) {
+void *safe_realloc_ary(void *p, size_t size, size_t count,
+		       const char *message) {
     if (count >= INT_MAX/size) {
 	fatal("array allocation overflow: %s", message);
     }
-    return safe_malloc(size*count, message);
+    assert(size && count);
+    p = realloc(p, size*count);
+    if (!p)
+	fatal_perror("%s", message);
+    return p;
+}
+
+void *safe_malloc_ary(size_t size, size_t count, const char *message) {
+    if (!size || !count)
+	return 0;
+    return safe_realloc_ary(0,size,count,message);
 }
 
 /* Convert a buffer into its MP_INT representation */
@@ -164,13 +177,17 @@ int32_t write_mpbin(MP_INT *a, uint8_t *buffer, int32_t buflen)
     return i;
 }
 
-void setcloexec(int fd) {
-    int r=fcntl(fd, F_GETFD);
-    if (r<0) fatal_perror("fcntl(,F_GETFD) failed");
-    r=fcntl(fd, F_SETFD, r|FD_CLOEXEC);
-    if (r<0) fatal_perror("fcntl(,F_SETFD,|FD_CLOEXEC) failed");
+#define DEFINE_SETFDFLAG(fn,FL,FLAG)					\
+void fn(int fd) {							\
+    int r=fcntl(fd, F_GET##FL);						\
+    if (r<0) fatal_perror("fcntl(,F_GET" #FL ") failed");		\
+    r=fcntl(fd, F_SET##FL, r|FLAG);					\
+    if (r<0) fatal_perror("fcntl(,F_SET" #FL ",|" #FLAG ") failed");	\
 }
 
+DEFINE_SETFDFLAG(setcloexec,FD,FD_CLOEXEC);
+DEFINE_SETFDFLAG(setnonblock,FL,O_NONBLOCK);
+
 void pipe_cloexec(int fd[2]) {
     int r=pipe(fd);
     if (r) fatal_perror("pipe");
@@ -194,15 +211,22 @@ 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]);
+}
+
 bool_t add_hook(uint32_t phase, hook_fn *fn, void *state)
 {
     struct phase_hook *h;
@@ -210,8 +234,7 @@ 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;
 }
 
@@ -268,6 +291,14 @@ 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));
@@ -581,3 +612,89 @@ int iaddr_socklen(const union iaddr *ia)
     default:       abort();
     }
 }
+
+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)
+#define BADBIT(b) \
+    if (!(revents & b)) ; else BAD(#b)
+    BADBIT(POLLERR);
+    BADBIT(POLLHUP);
+    /* POLLNVAL is handled by the event loop - see afterpoll_fn comment */
+#undef 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
+}