Fix occasional "Bad Request" response by waiting for data to be sent.

This also makes UtilGetDelim() and UtilGetLine() thread safe in that it
isn't setting a global errno. Of course, errno should be thread safe
already, but this makes it much less ambiguous.

src/HttpServer.c

@@ -41,6 +41,8 @@
 #include <arpa/inet.h>
 #include <fcntl.h>
 
+#include <errno.h>
+
 static const char ENABLE = 1;
 
 struct HttpServer
@@ -454,25 +456,38 @@ HttpServerWorkerThread(void *args)
         HashMap *requestParams;
         ssize_t requestPathLen;
 
+        int lineError = -1;
+
         ssize_t i = 0;
         HttpRequestMethod requestMethod;
 
         if (!fp)
         {
             /* Block for 1 millisecond before continuing so we don't
-             * murder the CPU */
+             * murder the CPU if the queue is empty. */
             UtilSleepMillis(1);
             continue;
         }
 
-        /* Get the first line of the request */
-        lineLen = UtilGetLine(&line, &lineSize, fp);
+        /* Get the first line of the request.
+         * 
+         * Every once in a while, we're too fast for the client. When this
+         * happens, UtilGetLine() sets lineError to EAGAIN. If we get
+         * EAGAIN, then clear the error on the stream and try again
+         * after 1ms. This is typically more than enough time for the
+         * client to send data. */
+        while ((lineLen = UtilGetLine(&line, &lineSize, fp, &lineError)) == -1
+               && lineError == EAGAIN)
+        {
+            clearerr(fp);
+            UtilSleepMillis(1);
+        }
+
         if (lineLen == -1)
         {
             goto bad_request;
         }
 
-
         requestMethodPtr = line;
         for (i = 0; i < lineLen; i++)
         {
@@ -535,7 +550,7 @@ HttpServerWorkerThread(void *args)
             goto internal_error;
         }
 
-        while ((lineLen = UtilGetLine(&line, &lineSize, fp)) != -1)
+        while ((lineLen = UtilGetLine(&line, &lineSize, fp, &lineError)) != -1)
         {
             char *headerKey;
             char *headerValue;

src/Util.c

@@ -31,8 +31,9 @@
 #include <ctype.h>
 #include <math.h>
 #include <time.h>
-#include <sys/time.h>
+
 #include <errno.h>
+#include <sys/time.h>
 #include <limits.h>
 
 unsigned long
@@ -179,7 +180,7 @@ UtilStringToBytes(char *str)
 }
 
 ssize_t
-UtilGetDelim(char **linePtr, size_t * n, int delim, FILE * stream)
+UtilGetDelim(char **linePtr, size_t * n, int delim, FILE * stream, int *err)
 {
     char *curPos, *newLinePtr;
     size_t newLinePtrLen;
@@ -187,7 +188,7 @@ UtilGetDelim(char **linePtr, size_t * n, int delim, FILE * stream)
 
     if (!linePtr || !n || !stream)
     {
-        errno = EINVAL;
+        *err = EINVAL;
         return -1;
     }
 
@@ -197,7 +198,7 @@ UtilGetDelim(char **linePtr, size_t * n, int delim, FILE * stream)
 
         if (!(*linePtr = Malloc(*n)))
         {
-            errno = ENOMEM;
+            *err = ENOMEM;
             return -1;
         }
     }
@@ -210,6 +211,7 @@ UtilGetDelim(char **linePtr, size_t * n, int delim, FILE * stream)
 
         if (ferror(stream) || (c == EOF && curPos == *linePtr))
         {
+            *err = errno;
             return -1;
         }
 
@@ -223,9 +225,9 @@ UtilGetDelim(char **linePtr, size_t * n, int delim, FILE * stream)
             if (SSIZE_MAX / 2 < *n)
             {
 #ifdef EOVERFLOW
-                errno = EOVERFLOW;
+                *err = EOVERFLOW;
 #else
-                errno = ERANGE;
+                *err = ERANGE;
 #endif
                 return -1;
             }
@@ -234,7 +236,7 @@ UtilGetDelim(char **linePtr, size_t * n, int delim, FILE * stream)
 
             if (!(newLinePtr = Realloc(*linePtr, newLinePtrLen)))
             {
-                errno = ENOMEM;
+                *err = ENOMEM;
                 return -1;
             }
 
@@ -256,7 +258,7 @@ UtilGetDelim(char **linePtr, size_t * n, int delim, FILE * stream)
 }
 
 ssize_t
-UtilGetLine(char **linePtr, size_t * n, FILE * stream)
+UtilGetLine(char **linePtr, size_t * n, FILE * stream, int *err)
 {
-    return UtilGetDelim(linePtr, n, '\n', stream);
+    return UtilGetDelim(linePtr, n, '\n', stream, err);
 }

src/include/Util.h

@@ -104,9 +104,9 @@ extern size_t
  UtilStringToBytes(char *);
 
 extern ssize_t
- UtilGetDelim(char **, size_t *, int, FILE *);
+ UtilGetDelim(char **, size_t *, int, FILE *, int *);
 
 extern ssize_t
- UtilGetLine(char **, size_t *, FILE *);
+ UtilGetLine(char **, size_t *, FILE *, int *);
 
 #endif                             /* TELODENDRIA_UTIL_H */