Read varint

lib/nghttp3_conv.c

@@ -66,8 +66,6 @@ const uint8_t *nghttp3_get_varint(int64_t *dest, const uint8_t *p) {
   }
 }
 
-int64_t nghttp3_get_varint_fb(const uint8_t *p) { return *p & 0x3f; }
-
 size_t nghttp3_get_varintlen(const uint8_t *p) {
   return (size_t)(1u << (*p >> 6));
 }

lib/nghttp3_conv.h

@@ -135,12 +135,6 @@ STIN uint16_t ntohs(uint16_t netshort) {
  */
 const uint8_t *nghttp3_get_varint(int64_t *dest, const uint8_t *p);
 
-/*
- * nghttp3_get_varint_fb reads first byte of encoded variable-length
- * integer from |p|.
- */
-int64_t nghttp3_get_varint_fb(const uint8_t *p);
-
 /*
  * nghttp3_get_varintlen returns the required number of bytes to read
  * variable-length integer starting at |p|.

lib/nghttp3_stream.c

@@ -181,42 +181,45 @@ void nghttp3_stream_read_state_reset(nghttp3_stream_read_state *rstate) {
 nghttp3_ssize nghttp3_read_varint(nghttp3_varint_read_state *rvint,
                                   const uint8_t *begin, const uint8_t *end,
                                   int fin) {
-  const uint8_t *orig_begin = begin;
-  size_t len;
+  size_t len, vlen;
+  uint8_t *p;
 
   assert(begin != end);
 
   if (rvint->left == 0) {
     assert(rvint->acc == 0);
 
-    len = nghttp3_get_varintlen(begin);
-    if (len <= (size_t)(end - begin)) {
+    vlen = nghttp3_get_varintlen(begin);
+    len = nghttp3_min_size(vlen, (size_t)(end - begin));
+    if (vlen <= len) {
       nghttp3_get_varint(&rvint->acc, begin);
-      return (nghttp3_ssize)len;
+      return (nghttp3_ssize)vlen;
     }
 
     if (fin) {
       return NGHTTP3_ERR_INVALID_ARGUMENT;
     }
 
-    rvint->acc = nghttp3_get_varint_fb(begin++);
-    rvint->left = len - 1;
-  }
+    p = (uint8_t *)&rvint->acc + (sizeof(rvint->acc) - vlen);
+    memcpy(p, begin, len);
+    *p &= 0x3f;
+    rvint->left = vlen - len;
 
-  len = nghttp3_min_size(rvint->left, (size_t)(end - begin));
-  end = begin + len;
-
-  for (; begin != end;) {
-    rvint->acc = (rvint->acc << 8) + *begin++;
+    return (nghttp3_ssize)len;
   }
 
+  len = nghttp3_min_size(rvint->left, (size_t)(end - begin));
+  p = (uint8_t *)&rvint->acc + (sizeof(rvint->acc) - rvint->left);
+  memcpy(p, begin, len);
   rvint->left -= len;
 
-  if (fin && rvint->left) {
+  if (rvint->left == 0) {
+    rvint->acc = (int64_t)nghttp3_ntohl64((uint64_t)rvint->acc);
+  } else if (fin) {
     return NGHTTP3_ERR_INVALID_ARGUMENT;
   }
 
-  return (nghttp3_ssize)(begin - orig_begin);
+  return (nghttp3_ssize)len;
 }
 
 int nghttp3_stream_frq_add(nghttp3_stream *stream,

tests/CMakeLists.txt

@@ -34,6 +34,7 @@ set(main_SOURCES
   main.c
   nghttp3_qpack_test.c
   nghttp3_conn_test.c
+  nghttp3_stream_test.c
   nghttp3_tnode_test.c
   nghttp3_http_test.c
   nghttp3_conv_test.c

tests/Makefile.am

@@ -30,6 +30,7 @@ OBJECTS = \
 	main.c \
 	nghttp3_qpack_test.c \
 	nghttp3_conn_test.c \
+	nghttp3_stream_test.c \
 	nghttp3_tnode_test.c \
 	nghttp3_http_test.c \
 	nghttp3_conv_test.c \
@@ -38,6 +39,7 @@ OBJECTS = \
 HFILES = \
 	nghttp3_qpack_test.h \
 	nghttp3_conn_test.h \
+	nghttp3_stream_test.h \
 	nghttp3_tnode_test.h \
 	nghttp3_http_test.h \
 	nghttp3_conv_test.h \

tests/main.c

@@ -33,13 +33,14 @@
 /* include test cases' include files here */
 #include "nghttp3_qpack_test.h"
 #include "nghttp3_conn_test.h"
+#include "nghttp3_stream_test.h"
 #include "nghttp3_tnode_test.h"
 #include "nghttp3_http_test.h"
 #include "nghttp3_conv_test.h"
 
 int main(int argc, char **argv) {
   const MunitSuite suites[] = {
-    qpack_suite, conn_suite, tnode_suite, http_suite, {0},
+    qpack_suite, conn_suite, stream_suite, tnode_suite, http_suite, {0},
   };
   const MunitSuite suite = {
     .prefix = "",

tests/nghttp3_stream_test.c

@@ -0,0 +1,181 @@
+/*
+ * nghttp3
+ *
+ * Copyright (c) 2025 nghttp3 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#include "nghttp3_stream_test.h"
+
+#include <stdio.h>
+#include <assert.h>
+
+#include "nghttp3_stream.h"
+#include "nghttp3_test_helper.h"
+
+static const MunitTest tests[] = {
+  munit_void_test(test_nghttp3_read_varint),
+  munit_test_end(),
+};
+
+const MunitSuite stream_suite = {
+  .prefix = "/stream",
+  .tests = tests,
+};
+
+void test_nghttp3_read_varint(void) {
+  nghttp3_varint_read_state rvint;
+  nghttp3_ssize nread;
+
+  {
+    /* 1 byte integer */
+    const uint8_t input[] = {0x3f};
+
+    nghttp3_varint_read_state_reset(&rvint);
+
+    nread =
+      nghttp3_read_varint(&rvint, input, input + sizeof(input), /* fin = */ 0);
+
+    assert_ptrdiff(1, ==, nread);
+    assert_size(0, ==, rvint.left);
+    assert_int64(63, ==, rvint.acc);
+  }
+
+  {
+    /* 1 byte integer with fin */
+    const uint8_t input[] = {0x3f};
+
+    nghttp3_varint_read_state_reset(&rvint);
+
+    nread =
+      nghttp3_read_varint(&rvint, input, input + sizeof(input), /* fin = */ 1);
+
+    assert_ptrdiff((nghttp3_ssize)sizeof(input), ==, nread);
+    assert_size(0, ==, rvint.left);
+    assert_int64(63, ==, rvint.acc);
+  }
+
+  {
+    /* 4 bytes integer */
+    const uint8_t input[] = {0xad, 0xa5, 0xcb, 0x03};
+
+    nghttp3_varint_read_state_reset(&rvint);
+
+    nread =
+      nghttp3_read_varint(&rvint, input, input + sizeof(input), /* fin = */ 0);
+
+    assert_ptrdiff((nghttp3_ssize)sizeof(input), ==, nread);
+    assert_size(0, ==, rvint.left);
+    assert_int64(0x2d << 24 | 0xa5 << 16 | 0xcb << 8 | 0x03, ==, rvint.acc);
+  }
+
+  {
+    /* 4 bytes integer but incomplete */
+    const uint8_t input[] = {0xad, 0xa5, 0xcb, 0x03};
+
+    nghttp3_varint_read_state_reset(&rvint);
+
+    nread = nghttp3_read_varint(&rvint, input, input + sizeof(input) - 1,
+                                /* fin = */ 0);
+
+    assert_ptrdiff((nghttp3_ssize)(sizeof(input) - 1), ==, nread);
+    assert_size(1, ==, rvint.left);
+
+    nread = nghttp3_read_varint(&rvint, input + sizeof(input) - 1,
+                                input + sizeof(input), /* fin = */ 1);
+
+    assert_ptrdiff(1, ==, nread);
+    assert_size(0, ==, rvint.left);
+    assert_int64(0x2d << 24 | 0xa5 << 16 | 0xcb << 8 | 0x03, ==, rvint.acc);
+  }
+
+  {
+    /* 4 bytes integer prematurely ended by fin */
+    const uint8_t input[] = {0xad, 0xa5, 0xcb};
+
+    nghttp3_varint_read_state_reset(&rvint);
+
+    nread =
+      nghttp3_read_varint(&rvint, input, input + sizeof(input), /* fin = */ 1);
+
+    assert_ptrdiff(NGHTTP3_ERR_INVALID_ARGUMENT, ==, nread);
+  }
+
+  {
+    /* 4 bytes integer prematurely ended by fin in the second input */
+    const uint8_t input[] = {0xad, 0xa5, 0xcb};
+
+    nghttp3_varint_read_state_reset(&rvint);
+
+    nread = nghttp3_read_varint(&rvint, input, input + (sizeof(input) - 1),
+                                /* fin = */ 0);
+
+    assert_ptrdiff((nghttp3_ssize)(sizeof(input) - 1), ==, nread);
+    assert_size(2, ==, rvint.left);
+
+    nread = nghttp3_read_varint(&rvint, input + (sizeof(input) - 1),
+                                input + sizeof(input),
+                                /* fin = */ 1);
+
+    assert_ptrdiff(NGHTTP3_ERR_INVALID_ARGUMENT, ==, nread);
+  }
+
+  {
+    /* 4 bytes integer + extra byte */
+    const uint8_t input[] = {0xad, 0xa5, 0xcb, 0x03, 0xff};
+
+    nghttp3_varint_read_state_reset(&rvint);
+
+    nread =
+      nghttp3_read_varint(&rvint, input, input + sizeof(input), /* fin = */ 0);
+
+    assert_ptrdiff((nghttp3_ssize)(sizeof(input) - 1), ==, nread);
+    assert_size(0, ==, rvint.left);
+    assert_int64(0x2d << 24 | 0xa5 << 16 | 0xcb << 8 | 0x03, ==, rvint.acc);
+  }
+
+  {
+    /* 8 bytes integer */
+    const uint8_t input[] = {0xed, 0xa5, 0xcb, 0x03, 0x90, 0xfc, 0x13, 0xd8};
+
+    nghttp3_varint_read_state_reset(&rvint);
+
+    nread =
+      nghttp3_read_varint(&rvint, input, input + sizeof(input), /* fin = */ 0);
+
+    assert_ptrdiff((nghttp3_ssize)sizeof(input), ==, nread);
+    assert_size(0, ==, rvint.left);
+    assert_int64(0x2dll << 56 | 0xa5ll << 48 | 0xcbll << 40 | 0x03ll << 32 |
+                   0x90ll << 24 | 0xfcll << 16 | 0x13ll << 8 | 0xd8ll,
+                 ==, rvint.acc);
+  }
+
+  {
+    /* 8 bytes integer prematurely ended by fin at the first byte */
+    const uint8_t input[] = {0xed};
+
+    nghttp3_varint_read_state_reset(&rvint);
+
+    nread =
+      nghttp3_read_varint(&rvint, input, input + sizeof(input), /* fin = */ 1);
+
+    assert_ptrdiff(NGHTTP3_ERR_INVALID_ARGUMENT, ==, nread);
+  }
+}

tests/nghttp3_stream_test.h

@@ -0,0 +1,40 @@
+/*
+ * nghttp3
+ *
+ * Copyright (c) 2025 nghttp3 contributors
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS BE
+ * LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN ACTION
+ * OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN CONNECTION
+ * WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE SOFTWARE.
+ */
+#ifndef NGHTTP3_STREAM_TEST_H
+#define NGHTTP3_STREAM_TEST_H
+
+#ifdef HAVE_CONFIG_H
+#  include <config.h>
+#endif /* defined(HAVE_CONFIG_H) */
+
+#define MUNIT_ENABLE_ASSERT_ALIASES
+
+#include "munit.h"
+
+extern const MunitSuite stream_suite;
+
+munit_void_test_decl(test_nghttp3_read_varint)
+
+#endif /* !defined(NGHTTP3_STREAM_TEST_H) */