diff --git a/allcing.h b/allcing.h
index 0ddf284..54e09be 100644
--- a/allcing.h
+++ b/allcing.h
@@ -15,10 +15,10 @@
 
 // ---- variable points
 #if !defined(ACG_NOW)
-# define ACG_NOW ((uint64_t) (clock()/CLOCKS_PER_SEC*10000000U))
+# define ACG_NOW ((uint64_t) ((double) clock()/CLOCKS_PER_SEC*1000000U))
 #endif
 #if !defined(ACG_TID)
-# define ACG_TID (0U)  // you should replace ACG_TID to log an actual TID
+# define ACG_TID (0x700FU)  // you should replace ACG_TID to log an actual TID
 #endif
 #if !defined(ACG_LOC_FULL)
 # define ACG_LOC_FULL (__FILE__ ":" ACG_UTIL_STR2(__func__) ":" ACG_UTIL_STR2(__LINE__))
@@ -33,11 +33,11 @@
 
 // ---- sugar syntax for logging
 #define ACG_BLOB_LITERAL(s, data) (  \
-    acg_stream_write_blob((s), sizeof((data)), (const uint8_t*) (data)) &&  \
+    acg_stream_write_chunk_blob((s), sizeof((data)), (const uint8_t*) (data)) &&  \
     ACG_FLUSH((s))  \
   )
 #define ACG_BLOB(s, size, data) (  \
-    acg_stream_write_blob((s), (size), (const uint8_t*) (data)) &&  \
+    acg_stream_write_chunk_blob((s), (size), (const uint8_t*) (data)) &&  \
     ACG_FLUSH((s))  \
   )
 #define ACG_BEGIN(s) (  \
@@ -89,6 +89,8 @@ struct acg_stream {
   void*    udata;
 };
 
+
+#if !defined(ACG_NO_WRITE_FUNCTIONS)
 static inline bool acg_stream_write_pad(struct acg_stream* s) {
   assert(NULL != s);
 
@@ -115,44 +117,31 @@ static inline bool acg_stream_write_uint(struct acg_stream* s, uint64_t v, uint8
   uint64_t* const c   = &s->cursor_bits;
 
   const uint8_t unit_data_bits = unit_bits - 1U;
-  while (v) {
+  do {
     if (s->size_bytes*8U - *c < unit_bits) {
       return false;
     }
 
-    const uint64_t next_v = v >> unit_data_bits;
-    acg_stream_write_bool(s, !!next_v);
-
     const uint8_t frag_bits = acg_util_umin(unit_data_bits, (8U - *c%8U)%8U);
     if (frag_bits > 0U) {
       buf[*c/8U] |= (v & acg_util_fullbits(frag_bits)) << (*c%8U);
       *c += frag_bits;
     }
 
-    const uint8_t  remain_bits = unit_data_bits - frag_bits;
-    const uint64_t v_part      = (v >> frag_bits) & acg_util_fullbits(remain_bits);
-    memcpy(&buf[*c/8U], &v_part, (remain_bits + 7U) / 8U);
-    *c += remain_bits;
+    const uint8_t remain_bits = unit_data_bits - frag_bits;
+    if (remain_bits > 0U) {
+      assert(*c%8U == 0U);
 
-    v = next_v;
-  }
+      const uint64_t v_part = (v >> frag_bits) & acg_util_fullbits(remain_bits);
+      memcpy(&buf[*c/8U], &v_part, (remain_bits + 7U) / 8U);
+      *c += remain_bits;
+    }
+
+    v >>= unit_data_bits;;
+    acg_stream_write_bool(s, !!v);
+  } while (v);
   return true;
 }
-static inline bool acg_stream_write_int(struct acg_stream* s, int64_t v, uint8_t unit_bits) {
-  assert(NULL != s);
-  assert(2U  <= unit_bits);
-  assert(65U >= unit_bits);
-
-  if (v >= 0U) {
-    return
-        acg_stream_write_bool(s, false) &&
-        acg_stream_write_uint(s, (uint64_t) v, unit_bits);
-  } else {
-    return
-        acg_stream_write_bool(s, true) &&
-        acg_stream_write_uint(s, (uint64_t) -v, unit_bits);
-  }
-}
 static inline bool acg_stream_write_blob(struct acg_stream* s, uint64_t size_bytes, const uint8_t* buf) {
   assert(NULL != s);
 
@@ -198,7 +187,7 @@ static inline bool acg_stream_write_chunk_blob(struct acg_stream* s, uint64_t si
 static inline bool acg_stream_write_chunk_ctx(struct acg_stream* s, uint64_t time, uint64_t tid) {
   assert(NULL != s);
   return
-      acg_stream_write_uint(s, ACG_CHUNK_LOC, ACG_UNITBITS_CHUNK_ID) &&
+      acg_stream_write_uint(s, ACG_CHUNK_CTX, ACG_UNITBITS_CHUNK_ID) &&
       acg_stream_write_uint(s, time, 64U) &&
       acg_stream_write_uint(s, tid,  16U);
 }
@@ -220,3 +209,97 @@ static inline bool acg_stream_write_chunk_check(struct acg_stream* s) {
   assert(NULL != s);
   return acg_stream_write_uint(s, ACG_CHUNK_CHECK, ACG_UNITBITS_CHUNK_ID);
 }
+#endif  // !defined(ACG_NO_WRITE_FUNCTIONS)
+
+
+#if !defined(ACG_NO_READ_FUNCTIONS)
+static inline bool acg_stream_read_pad(struct acg_stream* s) {
+  assert(NULL != s);
+
+  s->cursor_bits = (s->cursor_bits + 7U)/8U*8U;
+  return true;
+}
+static inline bool acg_stream_read_bool(struct acg_stream* s, bool* v) {
+  assert(NULL != s);
+  assert(NULL != v);
+
+  if (s->size_bytes*8U <= s->cursor_bits) {
+    return false;
+  }
+  uint64_t* const c = &s->cursor_bits;
+  *v = (s->buffer[*c/8U] >> (*c%8U)) & 1U;
+  ++*c;
+  return true;
+}
+static inline bool acg_stream_read_uint(struct acg_stream* s, uint64_t* v, uint8_t unit_bits) {
+  assert(NULL != s);
+  assert(NULL != v);
+  assert(2U  <= unit_bits);
+  assert(65U >= unit_bits);
+
+  *v = 0U;
+
+  const uint8_t unit_data_bits = unit_bits - 1U;
+
+  const uint8_t* const buf = s->buffer;
+  uint64_t* const      c   = &s->cursor_bits;
+
+  uint8_t v_offset_bits = 0U;
+  bool    cont_flag     = true;
+
+  while (cont_flag) {
+    if (s->size_bytes*8U < *c+unit_data_bits) {
+      return false;
+    }
+
+    const uint8_t frag_bits = acg_util_umin((8U - *c%8U)%8U, unit_data_bits);
+    if (frag_bits > 0U) {
+      const uint64_t v_part =
+          (buf[*c/8U] >> (*c%8U)) & acg_util_fullbits(frag_bits);
+      *v            |= v_part << v_offset_bits;
+      *c            += frag_bits;
+      v_offset_bits += frag_bits;
+    }
+
+    const uint8_t remain_bits = unit_data_bits - frag_bits;
+    if (remain_bits > 0U) {
+      assert(*c%8U == 0U);
+
+      uint64_t v_part = 0U;
+      memcpy(&v_part, &buf[*c/8U], (remain_bits+7U)/8U);
+      v_part &= acg_util_fullbits(remain_bits);
+
+      *v            |= v_part << v_offset_bits;
+      *c            += remain_bits;
+      v_offset_bits += remain_bits;
+    }
+
+    if (!acg_stream_read_bool(s, &cont_flag)) {
+      return false;
+    }
+  }
+  return true;
+}
+static inline bool acg_stream_read_blob(struct acg_stream* s, uint64_t* size, uint8_t** buf) {
+  assert(NULL != s);
+  assert(NULL != size);
+  assert(NULL != buf);
+
+  if (!acg_stream_read_uint(s, size, 8U)) {
+    return false;
+  }
+  if (!acg_stream_read_pad(s)) {
+    return false;
+  }
+
+  uint64_t* const c = &s->cursor_bits;
+
+  const uint64_t offset = *c/8U;
+  if (s->size_bytes < offset + *size) {
+    return false;
+  }
+  *buf  = &s->buffer[offset];
+  *c   += *size *8U;
+  return true;
+}
+#endif  // !defined(ACG_NO_READ_FUNCTIONS)
diff --git a/test.c b/test.c
index ead04a2..8b27e65 100644
--- a/test.c
+++ b/test.c
@@ -11,9 +11,9 @@
 
 
 int main(int, char**) {
-# define STREAM(size, offset)  \
+# define STREAM(size, offset, ...)  \
     (struct acg_stream) {  \
-      .buffer = (uint8_t[size]) {0U},  \
+      .buffer = (uint8_t[size]) {__VA_ARGS__ __VA_OPT__(,) 0U,},  \
       .size_bytes = (size),  \
       .cursor_bits = (offset),  \
     }
@@ -45,37 +45,30 @@ int main(int, char**) {
   /* acg_stream_write_uint / ends in a single byte */ {
     struct acg_stream s = STREAM(1024U, 0U);
     assert(acg_stream_write_uint(&s, 7U, 4U));
-    assert(s.buffer[0U] == 0x0EU);
+    assert(s.buffer[0U] == 0x07U);
     assert(s.cursor_bits == 4U);
   }
   /* acg_stream_write_uint / ends in a single byte with offset */ {
     struct acg_stream s = STREAM(1024U, 1U);
     assert(acg_stream_write_uint(&s, 7U, 4U));
-    assert(s.buffer[0U] == 0x1CU);
+    assert(s.buffer[0U] == 0x0EU);
     assert(s.cursor_bits == 5U);
   }
   /* acg_stream_write_uint / separated data bits */ {
     struct acg_stream s = STREAM(1024U, 6U);
     assert(acg_stream_write_uint(&s, 7U, 4U));
-    assert(s.buffer[0U] == 0x80U);
-    assert(s.buffer[1U] == 0x03U);
+    assert(s.buffer[0U] == 0xC0U);
+    assert(s.buffer[1U] == 0x01U);
     assert(s.cursor_bits == 10U);
   }
   /* acg_stream_write_uint / separated cont flag */ {
     struct acg_stream s = STREAM(1024U, 7U);
     assert(acg_stream_write_uint(&s, 7U, 4U));
-    assert(s.buffer[0U] == 0x00U);
-    assert(s.buffer[1U] == 0x07U);
+    assert(s.buffer[0U] == 0x80U);
+    assert(s.buffer[1U] == 0x03U);
     assert(s.cursor_bits == 11U);
   }
 
-  /* acg_stream_write_int */ {
-    struct acg_stream s = STREAM(1024U, 0U);
-    assert(acg_stream_write_int(&s, -1, 4U));
-    assert(s.buffer[0U] == 0x05U);
-    assert(s.cursor_bits == 5U);
-  }
-
   /* acg_stream_write_chunk_pad / without offset */ {
     struct acg_stream s = STREAM(1024U, 0U);
     assert(acg_stream_write_chunk_pad(&s));
@@ -88,8 +81,20 @@ int main(int, char**) {
     assert(s.cursor_bits == 8U);
   }
 
-  /* acg_stream_write_chunk_pad / without offset */ {
+  /* acg_stream_write_chunk_blob / without offset */ {
     struct acg_stream s = STREAM(1024U, 0U);
+    assert(acg_stream_write_chunk_blob(
+          &s, 4U, (uint8_t[]) {0x00, 0x01, 0x02, 0x03}));
+    assert(s.buffer[0U]  == 0x41);
+    assert(s.buffer[1U]  == 0x00);
+    assert(s.buffer[2U]  == 0x00);
+    assert(s.buffer[3U]  == 0x01);
+    assert(s.buffer[4U]  == 0x02);
+    assert(s.buffer[5U]  == 0x03);
+    assert(s.cursor_bits == 48U);
+  }
+  /* acg_stream_write_chunk_blob / with offset=1 */ {
+    struct acg_stream s = STREAM(1024U, 1U);
     assert(acg_stream_write_chunk_blob(
           &s, 4U, (uint8_t[]) {0x00, 0x01, 0x02, 0x03}));
     assert(s.buffer[0U]  == 0x82);
@@ -100,29 +105,65 @@ int main(int, char**) {
     assert(s.buffer[5U]  == 0x03);
     assert(s.cursor_bits == 48U);
   }
-  /* acg_stream_write_chunk_pad / with offset=1 */ {
-    struct acg_stream s = STREAM(1024U, 1U);
-    assert(acg_stream_write_chunk_blob(
-          &s, 4U, (uint8_t[]) {0x00, 0x01, 0x02, 0x03}));
-    assert(s.buffer[0U]  == 0x04);
-    assert(s.buffer[1U]  == 0x01);
-    assert(s.buffer[2U]  == 0x00);
-    assert(s.buffer[3U]  == 0x01);
-    assert(s.buffer[4U]  == 0x02);
-    assert(s.buffer[5U]  == 0x03);
-    assert(s.cursor_bits == 48U);
-  }
-  /* acg_stream_write_chunk_pad / with offset=4 */ {
+  /* acg_stream_write_chunk_blob / with offset=4 */ {
     struct acg_stream s = STREAM(1024U, 4U);
     assert(acg_stream_write_chunk_blob(
           &s, 4U, (uint8_t[]) {0x00, 0x01, 0x02, 0x03}));
-    assert(s.buffer[0U]  == 0x20);
-    assert(s.buffer[1U]  == 0x08);
+    assert(s.buffer[0U]  == 0x10);
+    assert(s.buffer[1U]  == 0x04);
     assert(s.buffer[2U]  == 0x00);
     assert(s.buffer[3U]  == 0x01);
     assert(s.buffer[4U]  == 0x02);
     assert(s.buffer[5U]  == 0x03);
     assert(s.cursor_bits == 48U);
   }
+
+  /* acg_stream_read_pad / without offset */ {
+    struct acg_stream s = STREAM(1024U, 0U);
+    assert(acg_stream_read_pad(&s));
+    assert(s.cursor_bits == 0U);
+  }
+  /* acg_stream_read_pad / with offset=1 */ {
+    struct acg_stream s = STREAM(1024U, 1U);
+    assert(acg_stream_read_pad(&s));
+    assert(s.cursor_bits == 8U);
+  }
+
+  /* acg_stream_read_bool / with value=false */ {
+    struct acg_stream s = STREAM(1024U, 0U);
+    bool v;
+    assert(acg_stream_read_bool(&s, &v));
+    assert(v == false);
+    assert(s.cursor_bits == 1U);
+  }
+  /* acg_stream_read_bool / with value=true */ {
+    struct acg_stream s = STREAM(1024U, 0U, 0x01U);
+    bool v;
+    assert(acg_stream_read_bool(&s, &v));
+    assert(v == true);
+    assert(s.cursor_bits == 1U);
+  }
+
+  /* acg_stream_read_uint / with a single unit */ {
+    struct acg_stream s = STREAM(1024U, 0U, 0x04U);
+    uint64_t v;
+    assert(acg_stream_read_uint(&s, &v, 4U));
+    assert(v == 4U);
+    assert(s.cursor_bits == 4U);
+  }
+  /* acg_stream_read_uint / with multi units */ {
+    struct acg_stream s = STREAM(1024U, 0U, 0x48U);
+    uint64_t v;
+    assert(acg_stream_read_uint(&s, &v, 4U));
+    assert(v == 32U);
+    assert(s.cursor_bits == 8U);
+  }
+  /* acg_stream_read_uint / with multi bytes */ {
+    struct acg_stream s = STREAM(1024U, 0U, 0x88U, 0x04U);
+    uint64_t v;
+    assert(acg_stream_read_uint(&s, &v, 4U));
+    assert(v == 256U);
+    assert(s.cursor_bits == 12U);
+  }
   return EXIT_SUCCESS;
 }