Allocate the buffer in the VDP state, default size PIPE_BUF.

src/vdfp_pipe.c

@@ -36,6 +36,7 @@
 #include <string.h>
 #include <stdlib.h>
 #include <poll.h>
+#include <limits.h>
 #include <sys/types.h>
 #include <sys/wait.h>
 
@@ -91,12 +92,18 @@ struct vdp_state {
 	unsigned		magic;
 #define PIPE_VDP_STATE_MAGIC 0xaeb87f5f
 	struct VPFX(pipe_vdp)	*obj;
+	char			*buf;
 	pid_t			chldpid;
 	int			chldin;
 	int			chldout;
 	int			chlderr;
 };
 
+/* XXX make bufsz configurable per object (and at runtime?) */
+static size_t default_bufsz = 0;
+
+#define DEFAULT_DEFAULT_BUFSZ (4096)
+
 /* VDP */
 
 static inline int
@@ -156,6 +163,13 @@ vdp_init(struct req *req, void **priv)
 		     "state: %s", obj->name, vstrerror(errno));
 		return (-1);
 	}
+	state->buf = malloc(default_bufsz);
+	if (state->buf == NULL) {
+		VSLb(req->vsl, SLT_Error, "vdfp_pipe: vdp %s: cannot allocate "
+		     "buffer size %zd: %s", obj->name, default_bufsz,
+		     vstrerror(errno));
+		return (-1);
+	}
 	*priv = state;
 	state->obj = obj;
 	state->chldpid = -1;
@@ -295,8 +309,6 @@ rw_child(struct req *req, struct vdp_state *state, enum vdp_action act,
 	struct pollfd fds[3];
 	int retval, nfds;
 	ssize_t nbytes;
-	// XXX allocate buf in state
-	char buf[4096];
 
 	CHECK_OBJ_NOTNULL(state->obj, PIPE_VDP_MAGIC);
 	AN(state->obj->name);
@@ -383,7 +395,7 @@ rw_child(struct req *req, struct vdp_state *state, enum vdp_action act,
 			assert(fds[i].fd == state->chldout
 			       || fds[i].fd == state->chlderr);
 			errno = 0;
-			nbytes = read(fds[i].fd, buf, 4096);
+			nbytes = read(fds[i].fd, state->buf, default_bufsz);
 			if (nbytes < 0) {
 				VSLb(req->vsl, SLT_Error, "vdfp_pipe: vdp %s:"
 				     " error reading %s from %s: %s",
@@ -399,7 +411,8 @@ rw_child(struct req *req, struct vdp_state *state, enum vdp_action act,
 				break;
 			}
 			if (fds[i].fd == state->chldout) {
-				retval = VDP_bytes(req, VDP_FLUSH, buf, nbytes);
+				retval = VDP_bytes(req, VDP_FLUSH, state->buf,
+						   nbytes);
 				if (retval < 0) {
 					close_all(state);
 					return (-1);
@@ -409,7 +422,7 @@ rw_child(struct req *req, struct vdp_state *state, enum vdp_action act,
 			// XXX write one line at a time
 			VSLb(req->vsl, SLT_Error, "vdfp_pipe: vdp %s: %s "
 			     "stderr ...", state->obj->name, state->obj->path);
-			VSLb_bin(req->vsl, SLT_Error, nbytes, buf);
+			VSLb_bin(req->vsl, SLT_Error, nbytes, state->buf);
 		}
 		if (len == 0)
 			break;
@@ -452,6 +465,8 @@ vdp_fini(struct req *req, void **priv)
 
 	if (state->chldpid != -1)
 		(void)check_pid(state, req->vsl, 0);
+	if (state->buf != NULL)
+		free(state->buf);
 	FREE_OBJ(state);
 	*priv = NULL;
 	return (0);
@@ -469,6 +484,16 @@ vmod_event(VRT_CTX, struct vmod_priv *priv, enum vcl_event_e e)
 	AN(priv);
 
 	switch(e) {
+	case VCL_EVENT_LOAD:
+		if (default_bufsz == 0) {
+#ifdef PIPE_BUF
+			default_bufsz = PIPE_BUF;
+#else
+			default_bufsz = DEFAULT_DEFAULT_BUFSZ;
+#endif
+			AN(default_bufsz);
+		}
+		return (0);
 	case VCL_EVENT_DISCARD:
 		AN(ctx->vcl);
 		map = VRBT_MIN(vdp_tree, &tree_h);
@@ -491,7 +516,6 @@ vmod_event(VRT_CTX, struct vmod_priv *priv, enum vcl_event_e e)
 			}
 		}
 		return (0);
-	case VCL_EVENT_LOAD:
 	case VCL_EVENT_WARM:
 	case VCL_EVENT_COLD:
 		return (0);