Replace uint8_t with a pb_byte_t typedef.

This supports platforms where uint8_t does not exist.
If you are using a custom pb_syshdr.h, this may require adding
definitions for uint_least8_t etc.

6 files changed, 111 insertions, 92 deletions

diff --git a/extra/pb_syshdr.h b/extra/pb_syshdr.h
index 1ff48230..55d06a3a 100644
--- a/extra/pb_syshdr.h
+++ b/extra/pb_syshdr.h
@@ -24,6 +24,14 @@ typedef signed int int32_t;
 typedef unsigned int uint32_t;
 typedef signed long long int64_t;
 typedef unsigned long long uint64_t;
+
+/* These are ok for most platforms, unless uint8_t is actually not available,
+ * in which case you should give the smallest available type. */
+typedef int8_t int_least8_t;
+typedef uint8_t uint_least8_t;
+typedef uint8_t uint_fast8_t;
+typedef int16_t int_least16_t;
+typedef uint16_t uint_least16_t;
 #endif
 
 /* stddef.h subset */
diff --git a/pb.h b/pb.h
index b72e3196..92c5a702 100644
--- a/pb.h
+++ b/pb.h
@@ -55,7 +55,7 @@
 /* Include all the system headers needed by nanopb. You will need the
  * definitions of the following:
  * - strlen, memcpy, memset functions
- * - [u]int8_t, [u]int16_t, [u]int32_t, [u]int64_t
+ * - [u]int_least8_t, uint_fast8_t, [u]int_least16_t, [u]int32_t, [u]int64_t
  * - size_t
  * - bool
  *
@@ -144,7 +144,7 @@
  * Most-significant 4 bits specify repeated/required/packed etc.
  */
 
-typedef uint8_t pb_type_t;
+typedef uint_least8_t pb_type_t;
 
 /**** Field data types ****/
 
@@ -201,18 +201,22 @@ typedef uint8_t pb_type_t;
  * and array counts.
  */
 #if defined(PB_FIELD_32BIT)
-#define PB_SIZE_MAX ((uint32_t)-1)
     typedef uint32_t pb_size_t;
     typedef int32_t pb_ssize_t;
 #elif defined(PB_FIELD_16BIT)
-#define PB_SIZE_MAX ((uint16_t)-1)
-    typedef uint16_t pb_size_t;
-    typedef int16_t pb_ssize_t;
+    typedef uint_least16_t pb_size_t;
+    typedef int_least16_t pb_ssize_t;
 #else
-#define PB_SIZE_MAX ((uint8_t)-1)
-    typedef uint8_t pb_size_t;
-    typedef int8_t pb_ssize_t;
+    typedef uint_least8_t pb_size_t;
+    typedef int_least8_t pb_ssize_t;
 #endif
+#define PB_SIZE_MAX ((pb_size_t)-1)
+
+/* Data type for storing encoded data and other byte streams.
+ * This typedef exists to support platforms where uint8_t does not exist.
+ * You can regard it as equivalent on uint8_t on other platforms.
+ */
+typedef uint_least8_t pb_byte_t;
 
 /* This structure is used in auto-generated constants
  * to specify struct fields.
@@ -252,12 +256,12 @@ PB_STATIC_ASSERT(sizeof(uint64_t) == 2 * sizeof(uint32_t), UINT64_T_WRONG_SIZE)
  * It has the number of bytes in the beginning, and after that an array.
  * Note that actual structs used will have a different length of bytes array.
  */
-#define PB_BYTES_ARRAY_T(n) struct { pb_size_t size; uint8_t bytes[n]; }
+#define PB_BYTES_ARRAY_T(n) struct { pb_size_t size; pb_byte_t bytes[n]; }
 #define PB_BYTES_ARRAY_T_ALLOCSIZE(n) ((size_t)n + offsetof(pb_bytes_array_t, bytes))
 
 struct pb_bytes_array_s {
     pb_size_t size;
-    uint8_t bytes[1];
+    pb_byte_t bytes[1];
 };
 typedef struct pb_bytes_array_s pb_bytes_array_t;
 
diff --git a/pb_decode.c b/pb_decode.c
index e7689806..b7a0093e 100644
--- a/pb_decode.c
+++ b/pb_decode.c
@@ -23,9 +23,9 @@
 
 typedef bool (*pb_decoder_t)(pb_istream_t *stream, const pb_field_t *field, void *dest) checkreturn;
 
-static bool checkreturn buf_read(pb_istream_t *stream, uint8_t *buf, size_t count);
+static bool checkreturn buf_read(pb_istream_t *stream, pb_byte_t *buf, size_t count);
 static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest);
-static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, uint8_t *buf, size_t *size);
+static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, pb_byte_t *buf, size_t *size);
 static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter);
 static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter);
 static bool checkreturn decode_field(pb_istream_t *stream, pb_wire_type_t wire_type, pb_field_iter_t *iter);
@@ -72,10 +72,10 @@ static const pb_decoder_t PB_DECODERS[PB_LTYPES_COUNT] = {
  * pb_istream_t implementation *
  *******************************/
 
-static bool checkreturn buf_read(pb_istream_t *stream, uint8_t *buf, size_t count)
+static bool checkreturn buf_read(pb_istream_t *stream, pb_byte_t *buf, size_t count)
 {
-    const uint8_t *source = (const uint8_t*)stream->state;
-    stream->state = (uint8_t*)stream->state + count;
+    const pb_byte_t *source = (const pb_byte_t*)stream->state;
+    stream->state = (pb_byte_t*)stream->state + count;
     
     if (buf != NULL)
     {
@@ -86,13 +86,13 @@ static bool checkreturn buf_read(pb_istream_t *stream, uint8_t *buf, size_t coun
     return true;
 }
 
-bool checkreturn pb_read(pb_istream_t *stream, uint8_t *buf, size_t count)
+bool checkreturn pb_read(pb_istream_t *stream, pb_byte_t *buf, size_t count)
 {
 #ifndef PB_BUFFER_ONLY
 	if (buf == NULL && stream->callback != buf_read)
 	{
 		/* Skip input bytes */
-		uint8_t tmp[16];
+		pb_byte_t tmp[16];
 		while (count > 16)
 		{
 			if (!pb_read(stream, tmp, 16))
@@ -122,7 +122,7 @@ bool checkreturn pb_read(pb_istream_t *stream, uint8_t *buf, size_t count)
 
 /* Read a single byte from input stream. buf may not be NULL.
  * This is an optimization for the varint decoding. */
-static bool checkreturn pb_readbyte(pb_istream_t *stream, uint8_t *buf)
+static bool checkreturn pb_readbyte(pb_istream_t *stream, pb_byte_t *buf)
 {
     if (stream->bytes_left == 0)
         PB_RETURN_ERROR(stream, "end-of-stream");
@@ -131,8 +131,8 @@ static bool checkreturn pb_readbyte(pb_istream_t *stream, uint8_t *buf)
     if (!stream->callback(stream, buf, 1))
         PB_RETURN_ERROR(stream, "io error");
 #else
-    *buf = *(const uint8_t*)stream->state;
-    stream->state = (uint8_t*)stream->state + 1;
+    *buf = *(const pb_byte_t*)stream->state;
+    stream->state = (pb_byte_t*)stream->state + 1;
 #endif
 
     stream->bytes_left--;
@@ -140,7 +140,7 @@ static bool checkreturn pb_readbyte(pb_istream_t *stream, uint8_t *buf)
     return true;    
 }
 
-pb_istream_t pb_istream_from_buffer(const uint8_t *buf, size_t bufsize)
+pb_istream_t pb_istream_from_buffer(const pb_byte_t *buf, size_t bufsize)
 {
     pb_istream_t stream;
     /* Cast away the const from buf without a compiler error.  We are
@@ -170,7 +170,7 @@ pb_istream_t pb_istream_from_buffer(const uint8_t *buf, size_t bufsize)
 
 static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest)
 {
-    uint8_t byte;
+    pb_byte_t byte;
     uint32_t result;
     
     if (!pb_readbyte(stream, &byte))
@@ -184,7 +184,7 @@ static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest)
     else
     {
         /* Multibyte case */
-        uint8_t bitpos = 7;
+        uint_fast8_t bitpos = 7;
         result = byte & 0x7F;
         
         do
@@ -196,7 +196,7 @@ static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest)
                 return false;
             
             result |= (uint32_t)(byte & 0x7F) << bitpos;
-            bitpos = (uint8_t)(bitpos + 7);
+            bitpos = (uint_fast8_t)(bitpos + 7);
         } while (byte & 0x80);
    }
    
@@ -206,8 +206,8 @@ static bool checkreturn pb_decode_varint32(pb_istream_t *stream, uint32_t *dest)
 
 bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest)
 {
-    uint8_t byte;
-    uint8_t bitpos = 0;
+    pb_byte_t byte;
+    uint_fast8_t bitpos = 0;
     uint64_t result = 0;
     
     do
@@ -219,7 +219,7 @@ bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest)
             return false;
 
         result |= (uint64_t)(byte & 0x7F) << bitpos;
-        bitpos = (uint8_t)(bitpos + 7);
+        bitpos = (uint_fast8_t)(bitpos + 7);
     } while (byte & 0x80);
     
     *dest = result;
@@ -228,7 +228,7 @@ bool checkreturn pb_decode_varint(pb_istream_t *stream, uint64_t *dest)
 
 bool checkreturn pb_skip_varint(pb_istream_t *stream)
 {
-    uint8_t byte;
+    pb_byte_t byte;
     do
     {
         if (!pb_read(stream, &byte, 1))
@@ -287,7 +287,7 @@ bool checkreturn pb_skip_field(pb_istream_t *stream, pb_wire_type_t wire_type)
 /* Read a raw value to buffer, for the purpose of passing it to callback as
  * a substream. Size is maximum size on call, and actual size on return.
  */
-static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, uint8_t *buf, size_t *size)
+static bool checkreturn read_raw_value(pb_istream_t *stream, pb_wire_type_t wire_type, pb_byte_t *buf, size_t *size)
 {
     size_t max_size = *size;
     switch (wire_type)
@@ -375,7 +375,7 @@ static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t
                 
                 while (substream.bytes_left > 0 && *size < iter->pos->array_size)
                 {
-                    void *pItem = (uint8_t*)iter->pData + iter->pos->data_size * (*size);
+                    void *pItem = (char*)iter->pData + iter->pos->data_size * (*size);
                     if (!func(&substream, iter->pos, pItem))
                     {
                         status = false;
@@ -394,7 +394,7 @@ static bool checkreturn decode_static_field(pb_istream_t *stream, pb_wire_type_t
             {
                 /* Repeated field */
                 pb_size_t *size = (pb_size_t*)iter->pSize;
-                void *pItem = (uint8_t*)iter->pData + iter->pos->data_size * (*size);
+                void *pItem = (char*)iter->pData + iter->pos->data_size * (*size);
                 if (*size >= iter->pos->array_size)
                     PB_RETURN_ERROR(stream, "array overflow");
                 
@@ -548,7 +548,7 @@ static bool checkreturn decode_pointer_field(pb_istream_t *stream, pb_wire_type_
                     }
 
                     /* Decode the array entry */
-                    pItem = *(uint8_t**)iter->pData + iter->pos->data_size * (*size);
+                    pItem = *(char**)iter->pData + iter->pos->data_size * (*size);
                     initialize_pointer_field(pItem, iter);
                     if (!func(&substream, iter->pos, pItem))
                     {
@@ -584,7 +584,7 @@ static bool checkreturn decode_pointer_field(pb_istream_t *stream, pb_wire_type_
                 if (!allocate_field(stream, iter->pData, iter->pos->data_size, *size))
                     return false;
             
-                pItem = *(uint8_t**)iter->pData + iter->pos->data_size * (*size - 1);
+                pItem = *(char**)iter->pData + iter->pos->data_size * (*size - 1);
                 initialize_pointer_field(pItem, iter);
                 return func(stream, iter->pos, pItem);
             }
@@ -631,7 +631,7 @@ static bool checkreturn decode_callback_field(pb_istream_t *stream, pb_wire_type
          * which in turn allows to use same callback for packed and
          * not-packed fields. */
         pb_istream_t substream;
-        uint8_t buffer[10];
+        pb_byte_t buffer[10];
         size_t size = sizeof(buffer);
         
         if (!read_raw_value(stream, wire_type, buffer, &size))
@@ -838,7 +838,8 @@ static void pb_message_set_to_defaults(const pb_field_t fields[], void *dest_str
 
 bool checkreturn pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[], void *dest_struct)
 {
-    uint8_t fields_seen[(PB_MAX_REQUIRED_FIELDS + 7) / 8] = {0, 0, 0, 0, 0, 0, 0, 0};
+    uint32_t fields_seen[(PB_MAX_REQUIRED_FIELDS + 31) / 32] = {0, 0};
+    const uint32_t allbits = ~(uint32_t)0;
     uint32_t extension_range_start = 0;
     pb_field_iter_t iter;
     
@@ -894,8 +895,8 @@ bool checkreturn pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[
         if (PB_HTYPE(iter.pos->type) == PB_HTYPE_REQUIRED
             && iter.required_field_index < PB_MAX_REQUIRED_FIELDS)
         {
-            uint8_t tmp = (uint8_t)(1 << (iter.required_field_index & 7));
-            fields_seen[iter.required_field_index >> 3] |= tmp;
+            uint32_t tmp = ((uint32_t)1 << (iter.required_field_index & 31));
+            fields_seen[iter.required_field_index >> 5] |= tmp;
         }
             
         if (!decode_field(stream, wire_type, &iter))
@@ -920,16 +921,19 @@ bool checkreturn pb_decode_noinit(pb_istream_t *stream, const pb_field_t fields[
         if (PB_HTYPE(last_type) == PB_HTYPE_REQUIRED && iter.pos->tag != 0)
             req_field_count++;
         
-        /* Check the whole bytes */
-        for (i = 0; i < (req_field_count >> 3); i++)
+        if (req_field_count > 0)
         {
-            if (fields_seen[i] != 0xFF)
+            /* Check the whole words */
+            for (i = 0; i < (req_field_count >> 5); i++)
+            {
+                if (fields_seen[i] != allbits)
+                    PB_RETURN_ERROR(stream, "missing required field");
+            }
+            
+            /* Check the remaining bits */
+            if (fields_seen[req_field_count >> 5] != (allbits >> (32 - (req_field_count & 31))))
                 PB_RETURN_ERROR(stream, "missing required field");
         }
-        
-        /* Check the remaining bits */
-        if (fields_seen[req_field_count >> 3] != (0xFF >> (8 - (req_field_count & 7))))
-            PB_RETURN_ERROR(stream, "missing required field");
     }
     
     return true;
@@ -1038,7 +1042,7 @@ static void pb_release_single_field(const pb_field_iter_t *iter)
             while (count--)
             {
                 pb_release((const pb_field_t*)iter->pos->ptr, pItem);
-                pItem = (uint8_t*)pItem + iter->pos->data_size;
+                pItem = (char*)pItem + iter->pos->data_size;
             }
         }
     }
@@ -1106,7 +1110,7 @@ bool pb_decode_svarint(pb_istream_t *stream, int64_t *dest)
 
 bool pb_decode_fixed32(pb_istream_t *stream, void *dest)
 {
-    uint8_t bytes[4];
+    pb_byte_t bytes[4];
 
     if (!pb_read(stream, bytes, 4))
         return false;
@@ -1120,7 +1124,7 @@ bool pb_decode_fixed32(pb_istream_t *stream, void *dest)
 
 bool pb_decode_fixed64(pb_istream_t *stream, void *dest)
 {
-    uint8_t bytes[8];
+    pb_byte_t bytes[8];
 
     if (!pb_read(stream, bytes, 8))
         return false;
@@ -1179,8 +1183,8 @@ static bool checkreturn pb_dec_uvarint(pb_istream_t *stream, const pb_field_t *f
     
     switch (field->data_size)
     {
-        case 1: clamped = *(uint8_t*)dest = (uint8_t)value; break;
-        case 2: clamped = *(uint16_t*)dest = (uint16_t)value; break;
+        case 1: clamped = *(uint_least8_t*)dest = (uint_least8_t)value; break;
+        case 2: clamped = *(uint_least16_t*)dest = (uint_least16_t)value; break;
         case 4: clamped = *(uint32_t*)dest = (uint32_t)value; break;
         case 8: clamped = *(uint64_t*)dest = value; break;
         default: PB_RETURN_ERROR(stream, "invalid data_size");
@@ -1200,8 +1204,8 @@ static bool checkreturn pb_dec_svarint(pb_istream_t *stream, const pb_field_t *f
     
     switch (field->data_size)
     {
-        case 1: clamped = *(int8_t*)dest = (int8_t)value; break;
-        case 2: clamped = *(int16_t*)dest = (int16_t)value; break;
+        case 1: clamped = *(int_least8_t*)dest = (int_least8_t)value; break;
+        case 2: clamped = *(int_least16_t*)dest = (int_least16_t)value; break;
         case 4: clamped = *(int32_t*)dest = (int32_t)value; break;
         case 8: clamped = *(int64_t*)dest = value; break;
         default: PB_RETURN_ERROR(stream, "invalid data_size");
@@ -1292,8 +1296,8 @@ static bool checkreturn pb_dec_string(pb_istream_t *stream, const pb_field_t *fi
             PB_RETURN_ERROR(stream, "string overflow");
     }
     
-    status = pb_read(stream, (uint8_t*)dest, size);
-    *((uint8_t*)dest + size) = 0;
+    status = pb_read(stream, (pb_byte_t*)dest, size);
+    *((pb_byte_t*)dest + size) = 0;
     return status;
 }
 
diff --git a/pb_decode.h b/pb_decode.h
index 16de3e04..1d9bb194 100644
--- a/pb_decode.h
+++ b/pb_decode.h
@@ -34,7 +34,7 @@ struct pb_istream_s
      */
     int *callback;
 #else
-    bool (*callback)(pb_istream_t *stream, uint8_t *buf, size_t count);
+    bool (*callback)(pb_istream_t *stream, pb_byte_t *buf, size_t count);
 #endif
 
     void *state; /* Free field for use by callback implementation */
@@ -103,12 +103,12 @@ void pb_release(const pb_field_t fields[], void *dest_struct);
  * Alternatively, you can use a custom stream that reads directly from e.g.
  * a file or a network socket.
  */
-pb_istream_t pb_istream_from_buffer(const uint8_t *buf, size_t bufsize);
+pb_istream_t pb_istream_from_buffer(const pb_byte_t *buf, size_t bufsize);
 
 /* Function to read from a pb_istream_t. You can use this if you need to
  * read some custom header data, or to read data in field callbacks.
  */
-bool pb_read(pb_istream_t *stream, uint8_t *buf, size_t count);
+bool pb_read(pb_istream_t *stream, pb_byte_t *buf, size_t count);
 
 
 /************************************************
diff --git a/pb_encode.c b/pb_encode.c
index 14e657e9..95683751 100644
--- a/pb_encode.c
+++ b/pb_encode.c
@@ -22,7 +22,7 @@
  **************************************/
 typedef bool (*pb_encoder_t)(pb_ostream_t *stream, const pb_field_t *field, const void *src) checkreturn;
 
-static bool checkreturn buf_write(pb_ostream_t *stream, const uint8_t *buf, size_t count);
+static bool checkreturn buf_write(pb_ostream_t *stream, const pb_byte_t *buf, size_t count);
 static bool checkreturn encode_array(pb_ostream_t *stream, const pb_field_t *field, const void *pData, size_t count, pb_encoder_t func);
 static bool checkreturn encode_field(pb_ostream_t *stream, const pb_field_t *field, const void *pData);
 static bool checkreturn default_extension_encoder(pb_ostream_t *stream, const pb_extension_t *extension);
@@ -56,9 +56,9 @@ static const pb_encoder_t PB_ENCODERS[PB_LTYPES_COUNT] = {
  * pb_ostream_t implementation *
  *******************************/
 
-static bool checkreturn buf_write(pb_ostream_t *stream, const uint8_t *buf, size_t count)
+static bool checkreturn buf_write(pb_ostream_t *stream, const pb_byte_t *buf, size_t count)
 {
-    uint8_t *dest = (uint8_t*)stream->state;
+    pb_byte_t *dest = (pb_byte_t*)stream->state;
     stream->state = dest + count;
     
     while (count--)
@@ -67,7 +67,7 @@ static bool checkreturn buf_write(pb_ostream_t *stream, const uint8_t *buf, size
     return true;
 }
 
-pb_ostream_t pb_ostream_from_buffer(uint8_t *buf, size_t bufsize)
+pb_ostream_t pb_ostream_from_buffer(pb_byte_t *buf, size_t bufsize)
 {
     pb_ostream_t stream;
 #ifdef PB_BUFFER_ONLY
@@ -84,7 +84,7 @@ pb_ostream_t pb_ostream_from_buffer(uint8_t *buf, size_t bufsize)
     return stream;
 }
 
-bool checkreturn pb_write(pb_ostream_t *stream, const uint8_t *buf, size_t count)
+bool checkreturn pb_write(pb_ostream_t *stream, const pb_byte_t *buf, size_t count)
 {
     if (stream->callback != NULL)
     {
@@ -413,15 +413,18 @@ bool pb_get_encoded_size(size_t *size, const pb_field_t fields[], const void *sr
  ********************/
 bool checkreturn pb_encode_varint(pb_ostream_t *stream, uint64_t value)
 {
-    uint8_t buffer[10];
+    pb_byte_t buffer[10];
     size_t i = 0;
     
-    if (value == 0)
-        return pb_write(stream, (uint8_t*)&value, 1);
+    if (value <= 0x7F)
+    {
+        pb_byte_t v = (pb_byte_t)value;
+        return pb_write(stream, &v, 1);
+    }
     
     while (value)
     {
-        buffer[i] = (uint8_t)((value & 0x7F) | 0x80);
+        buffer[i] = (pb_byte_t)((value & 0x7F) | 0x80);
         value >>= 7;
         i++;
     }
@@ -444,26 +447,26 @@ bool checkreturn pb_encode_svarint(pb_ostream_t *stream, int64_t value)
 bool checkreturn pb_encode_fixed32(pb_ostream_t *stream, const void *value)
 {
     uint32_t val = *(const uint32_t*)value;
-    uint8_t bytes[4];
-    bytes[0] = (uint8_t)(val & 0xFF);
-    bytes[1] = (uint8_t)((val >> 8) & 0xFF);
-    bytes[2] = (uint8_t)((val >> 16) & 0xFF);
-    bytes[3] = (uint8_t)((val >> 24) & 0xFF);
+    pb_byte_t bytes[4];
+    bytes[0] = (pb_byte_t)(val & 0xFF);
+    bytes[1] = (pb_byte_t)((val >> 8) & 0xFF);
+    bytes[2] = (pb_byte_t)((val >> 16) & 0xFF);
+    bytes[3] = (pb_byte_t)((val >> 24) & 0xFF);
     return pb_write(stream, bytes, 4);
 }
 
 bool checkreturn pb_encode_fixed64(pb_ostream_t *stream, const void *value)
 {
     uint64_t val = *(const uint64_t*)value;
-    uint8_t bytes[8];
-    bytes[0] = (uint8_t)(val & 0xFF);
-    bytes[1] = (uint8_t)((val >> 8) & 0xFF);
-    bytes[2] = (uint8_t)((val >> 16) & 0xFF);
-    bytes[3] = (uint8_t)((val >> 24) & 0xFF);
-    bytes[4] = (uint8_t)((val >> 32) & 0xFF);
-    bytes[5] = (uint8_t)((val >> 40) & 0xFF);
-    bytes[6] = (uint8_t)((val >> 48) & 0xFF);
-    bytes[7] = (uint8_t)((val >> 56) & 0xFF);
+    pb_byte_t bytes[8];
+    bytes[0] = (pb_byte_t)(val & 0xFF);
+    bytes[1] = (pb_byte_t)((val >> 8) & 0xFF);
+    bytes[2] = (pb_byte_t)((val >> 16) & 0xFF);
+    bytes[3] = (pb_byte_t)((val >> 24) & 0xFF);
+    bytes[4] = (pb_byte_t)((val >> 32) & 0xFF);
+    bytes[5] = (pb_byte_t)((val >> 40) & 0xFF);
+    bytes[6] = (pb_byte_t)((val >> 48) & 0xFF);
+    bytes[7] = (pb_byte_t)((val >> 56) & 0xFF);
     return pb_write(stream, bytes, 8);
 }
 
@@ -505,7 +508,7 @@ bool checkreturn pb_encode_tag_for_field(pb_ostream_t *stream, const pb_field_t
     return pb_encode_tag(stream, wiretype, field->tag);
 }
 
-bool checkreturn pb_encode_string(pb_ostream_t *stream, const uint8_t *buffer, size_t size)
+bool checkreturn pb_encode_string(pb_ostream_t *stream, const pb_byte_t *buffer, size_t size)
 {
     if (!pb_encode_varint(stream, (uint64_t)size))
         return false;
@@ -573,8 +576,8 @@ static bool checkreturn pb_enc_varint(pb_ostream_t *stream, const pb_field_t *fi
      * or enums, and for int_size option. */
     switch (field->data_size)
     {
-        case 1: value = *(const int8_t*)src; break;
-        case 2: value = *(const int16_t*)src; break;
+        case 1: value = *(const int_least8_t*)src; break;
+        case 2: value = *(const int_least16_t*)src; break;
         case 4: value = *(const int32_t*)src; break;
         case 8: value = *(const int64_t*)src; break;
         default: PB_RETURN_ERROR(stream, "invalid data_size");
@@ -589,8 +592,8 @@ static bool checkreturn pb_enc_uvarint(pb_ostream_t *stream, const pb_field_t *f
     
     switch (field->data_size)
     {
-        case 1: value = *(const uint8_t*)src; break;
-        case 2: value = *(const uint16_t*)src; break;
+        case 1: value = *(const uint_least8_t*)src; break;
+        case 2: value = *(const uint_least16_t*)src; break;
         case 4: value = *(const uint32_t*)src; break;
         case 8: value = *(const uint64_t*)src; break;
         default: PB_RETURN_ERROR(stream, "invalid data_size");
@@ -605,8 +608,8 @@ static bool checkreturn pb_enc_svarint(pb_ostream_t *stream, const pb_field_t *f
     
     switch (field->data_size)
     {
-        case 1: value = *(const int8_t*)src; break;
-        case 2: value = *(const int16_t*)src; break;
+        case 1: value = *(const int_least8_t*)src; break;
+        case 2: value = *(const int_least16_t*)src; break;
         case 4: value = *(const int32_t*)src; break;
         case 8: value = *(const int64_t*)src; break;
         default: PB_RETURN_ERROR(stream, "invalid data_size");
@@ -669,7 +672,7 @@ static bool checkreturn pb_enc_string(pb_ostream_t *stream, const pb_field_t *fi
         }
     }
 
-    return pb_encode_string(stream, (const uint8_t*)src, size);
+    return pb_encode_string(stream, (const pb_byte_t*)src, size);
 }
 
 static bool checkreturn pb_enc_submessage(pb_ostream_t *stream, const pb_field_t *field, const void *src)
diff --git a/pb_encode.h b/pb_encode.h
index e992c8dc..d9909fb0 100644
--- a/pb_encode.h
+++ b/pb_encode.h
@@ -35,7 +35,7 @@ struct pb_ostream_s
      */
     int *callback;
 #else
-    bool (*callback)(pb_ostream_t *stream, const uint8_t *buf, size_t count);
+    bool (*callback)(pb_ostream_t *stream, const pb_byte_t *buf, size_t count);
 #endif
     void *state;          /* Free field for use by callback implementation. */
     size_t max_size;      /* Limit number of output bytes written (or use SIZE_MAX). */
@@ -86,7 +86,7 @@ bool pb_get_encoded_size(size_t *size, const pb_field_t fields[], const void *sr
  * Alternatively, you can use a custom stream that writes directly to e.g.
  * a file or a network socket.
  */
-pb_ostream_t pb_ostream_from_buffer(uint8_t *buf, size_t bufsize);
+pb_ostream_t pb_ostream_from_buffer(pb_byte_t *buf, size_t bufsize);
 
 /* Pseudo-stream for measuring the size of a message without actually storing
  * the encoded data.
@@ -106,7 +106,7 @@ pb_ostream_t pb_ostream_from_buffer(uint8_t *buf, size_t bufsize);
 /* Function to write into a pb_ostream_t stream. You can use this if you need
  * to append or prepend some custom headers to the message.
  */
-bool pb_write(pb_ostream_t *stream, const uint8_t *buf, size_t count);
+bool pb_write(pb_ostream_t *stream, const pb_byte_t *buf, size_t count);
 
 
 /************************************************
@@ -130,7 +130,7 @@ bool pb_encode_varint(pb_ostream_t *stream, uint64_t value);
 bool pb_encode_svarint(pb_ostream_t *stream, int64_t value);
 
 /* Encode a string or bytes type field. For strings, pass strlen(s) as size. */
-bool pb_encode_string(pb_ostream_t *stream, const uint8_t *buffer, size_t size);
+bool pb_encode_string(pb_ostream_t *stream, const pb_byte_t *buffer, size_t size);
 
 /* Encode a fixed32, sfixed32 or float value.
  * You need to pass a pointer to a 4-byte wide C variable. */