Implemented the file dpi based on select() (removed its pthreads dependency)

It should be faster and use less resources.

1 files changed, 66 insertions, 20 deletions

diff --git a/dpip/dpip.c b/dpip/dpip.c
index 5228f8de..b7332e72 100644
--- a/dpip/dpip.c
+++ b/dpip/dpip.c
@@ -22,6 +22,9 @@
 #include "dpip.h"
 #include "d_size.h"
 
+//#define RBUF_SZ 16384
+#define RBUF_SZ 1
+
 #define DPIP_TAG_END            " '>"
 #define DPIP_MODE_SWITCH_TAG    "cmd='start_send_page' "
 #define MSG_ERR(...)            fprintf(stderr, "[dpip]: " __VA_ARGS__)
@@ -292,27 +295,24 @@ int a_Dpip_dsh_write_str(Dsh *dsh, int flush, const char *str)
 }
 
 /*
- * Read new data from the socket into our buffer.
- * Used by both blocking and non-blocking IO.
+ * Read raw data from the socket into our buffer without blocking.
  */
-static void Dpip_dsh_read(Dsh *dsh)
+static void Dpip_dsh_read_nb(Dsh *dsh)
 {
-//#define LBUF_SZ 16384
-#define LBUF_SZ 1
-
    ssize_t st;
    int old_flags, blocking;
-   char buf[LBUF_SZ];
+   char buf[RBUF_SZ];
 
    blocking = !(dsh->mode & DPIP_NONBLOCK);
    if (blocking) {
+      /* set NONBLOCKING temporarily... */
       old_flags = fcntl(dsh->fd_in, F_GETFL);
+      fcntl(dsh->fd_in, F_SETFL, O_NONBLOCK | old_flags);
    }
 
    while (1) {
-      /* can't use fread() */
       do
-         st = read(dsh->fd_in, buf, LBUF_SZ);
+         st = read(dsh->fd_in, buf, RBUF_SZ);
       while (st < 0 && errno == EINTR);
 
       if (st < 0) {
@@ -330,10 +330,6 @@ static void Dpip_dsh_read(Dsh *dsh)
       } else {
          /* append to buf */
          dStr_append_l(dsh->rd_dbuf, buf, st);
-         if (blocking) {
-            /* set NONBLOCKING temporarily... */
-            fcntl(dsh->fd_in, F_SETFL, O_NONBLOCK | old_flags);
-         }
       }
    }
 
@@ -344,23 +340,73 @@ static void Dpip_dsh_read(Dsh *dsh)
 }
 
 /*
+ * Read raw data from the socket into our buffer in BLOCKING mode.
+ */
+static void Dpip_dsh_read(Dsh *dsh)
+{
+
+   ssize_t st;
+   int old_flags, non_blocking;
+   char buf[RBUF_SZ];
+
+   non_blocking = (dsh->mode & DPIP_NONBLOCK);
+   if (non_blocking) {
+      /* set blocking mode temporarily */
+      old_flags = fcntl(dsh->fd_in, F_GETFL);
+      fcntl(dsh->fd_in, F_SETFL, old_flags);
+   }
+
+   while (1) {
+      do
+         st = read(dsh->fd_in, buf, RBUF_SZ);
+      while (st < 0 && errno == EINTR);
+
+      if (st < 0) {
+         MSG_ERR("[Dpip_dsh_read] %s\n", dStrerror(errno));
+         dsh->status = DPIP_ERROR;
+         break;
+      } else if (st == 0) {
+         dsh->status = DPIP_EOF;
+         break;
+      } else {
+         /* append to buf */
+         dStr_append_l(dsh->rd_dbuf, buf, st);
+         break;
+      }
+   }
+
+   if (non_blocking) {
+      /* restore non blocking mode */
+      fcntl(dsh->fd_in, F_SETFL, old_flags);
+   }
+
+   /* assert there's no more data in the wire... */
+   Dpip_dsh_read_nb(dsh);
+}
+
+/*
  * Return a newlly allocated string with the next dpip token in the socket.
  * Return value: token string on success, NULL otherwise
  */
-char *a_Dpip_dsh_read_token(Dsh *dsh)
+char *a_Dpip_dsh_read_token(Dsh *dsh, int blocking)
 {
    char *p, *ret = NULL;
 
+   /* Read all available data without blocking */
+   Dpip_dsh_read_nb(dsh);
+
    /* switch mode upon request */
    if (dsh->mode & DPIP_LAST_TAG)
       dsh->mode = DPIP_RAW;
 
-   /* Only read from socket when there's no data in buffer or
-    * the tag is incomplete */
-   if (dsh->rd_dbuf->len == 0 ||
-       (dsh->mode & DPIP_TAG &&
-        !(p = strstr(dsh->rd_dbuf->str, DPIP_TAG_END)))) {
-      Dpip_dsh_read(dsh);
+   if (blocking && dsh->mode & DPIP_TAG) {
+      /* Only wait for data when the tag is incomplete */
+      if (!strstr(dsh->rd_dbuf->str, DPIP_TAG_END)) {
+         do {
+            Dpip_dsh_read(dsh);
+            p = strstr(dsh->rd_dbuf->str, DPIP_TAG_END);
+         } while (!p && dsh->status == EAGAIN);
+      }
    }
 
    if (dsh->mode & DPIP_TAG) {