X-Git-Url: http://xvm.mit.edu/gitweb/invirt/third/libt4.git/blobdiff_plain/2546a41ad36fdc9ef6471cb35a1d56930ae1b527..5d99dbf06a14904944f5593c63705934bdfdcfb7:/rpc/marshall.h?ds=sidebyside

diff --git a/rpc/marshall.h b/rpc/marshall.h
index abeaae7..d7f1dff 100644
--- a/rpc/marshall.h
+++ b/rpc/marshall.h
@@ -1,261 +1,177 @@
 #ifndef marshall_h
 #define marshall_h
 
-#include <iostream>
-#include <sstream>
-#include <string>
-#include <vector>
-#include <map>
-#include <stdlib.h>
-#include <string.h>
-#include <cstddef>
-#include <inttypes.h>
-#include "lang/verify.h"
+#include "types.h"
+
+// for structs or classes containing a MEMBERS declaration
+class marshall;
+class unmarshall;
+#define FORWARD_MARSHALLABLE(_c_) \
+extern unmarshall & operator>>(unmarshall &u, typename remove_reference<_c_>::type &a); \
+extern marshall & operator<<(marshall &m, const _c_ a);
+#define MARSHALLABLE(_c_) \
+inline unmarshall & operator>>(unmarshall &u, _c_ &a) { return u >> a._tuple_(); } \
+inline marshall & operator<<(marshall &m, const _c_ a) { return m << a._tuple_(); }
+
+// for plain old data
+#define MARSHALL_RAW_NETWORK_ORDER_AS(_c_, _d_) \
+marshall & operator<<(marshall &m, _c_ x) { _d_ y = hton((_d_)x); m.rawbytes(&y, sizeof(_d_)); return m; } \
+unmarshall & operator>>(unmarshall &u, _c_ &x) { _d_ y; u.rawbytes(&y, sizeof(_d_)); x = (_c_)ntoh(y); return u; }
+
+#define MARSHALL_RAW_NETWORK_ORDER(_c_) MARSHALL_RAW_NETWORK_ORDER_AS(_c_, _c_)
 
 using proc_t = uint32_t;
 using status_t = int32_t;
 
 struct request_header {
-    request_header(int x=0, proc_t p=0, unsigned c=0, unsigned s=0, int xi=0) :
-        xid(x), proc(p), clt_nonce(c), srv_nonce(s), xid_rep(xi) {}
     int xid;
     proc_t proc;
     unsigned int clt_nonce;
     unsigned int srv_nonce;
     int xid_rep;
+
+    MEMBERS(xid, proc, clt_nonce, srv_nonce, xid_rep)
 };
 
+FORWARD_MARSHALLABLE(request_header)
+ENDIAN_SWAPPABLE(request_header)
+
 struct reply_header {
-    reply_header(int x=0, int r=0): xid(x), ret(r) {}
     int xid;
     int ret;
-};
-
-template<class T> inline T hton(T t);
 
-constexpr union { uint32_t i; uint8_t is_little_endian; } endianness{1};
-
-template<> inline uint8_t hton(uint8_t t) { return t; }
-template<> inline int8_t hton(int8_t t) { return t; }
-template<> inline uint16_t hton(uint16_t t) { return htons(t); }
-template<> inline int16_t hton(int16_t t) { return (int16_t)htons((uint16_t)t); }
-template<> inline uint32_t hton(uint32_t t) { return htonl(t); }
-template<> inline int32_t hton(int32_t t) { return (int32_t)htonl((uint32_t)t); }
-template<> inline uint64_t hton(uint64_t t) {
-    if (!endianness.is_little_endian)
-        return t;
-    return (uint64_t)htonl((uint32_t)(t >> 32)) | ((uint64_t)htonl((uint32_t)t) << 32);
-}
-template<> inline int64_t hton(int64_t t) { return (int64_t)hton((uint64_t)t); }
-template<> inline request_header hton(request_header h) { return {hton(h.xid), hton(h.proc), hton(h.clt_nonce), hton(h.srv_nonce), hton(h.xid_rep)}; }
-template<> inline reply_header hton(reply_header h) { return {hton(h.xid), hton(h.ret)}; }
+    MEMBERS(xid, ret)
+};
 
-template <class T> inline T ntoh(T t) { return hton(t); }
+FORWARD_MARSHALLABLE(reply_header)
+ENDIAN_SWAPPABLE(reply_header)
 
 typedef int rpc_sz_t;
 
-//size of initial buffer allocation
-#define DEFAULT_RPC_SZ 1024
-#define RPC_HEADER_SZ (std::max(sizeof(request_header), sizeof(reply_header)) + sizeof(rpc_sz_t))
+const size_t RPC_HEADER_SZ = max(sizeof(request_header), sizeof(reply_header)) + sizeof(rpc_sz_t);
+const size_t DEFAULT_RPC_SZ = 1024; // size of initial buffer allocation
+
+// Template parameter pack expansion is not allowed in certain contexts, but
+// brace initializers (for instance, calls to constructors of empty structs)
+// are fair game.  
+struct pass { template <typename... Args> inline pass(Args&&...) {} };
 
 class marshall {
     private:
-        char *buf_;     // Base of the raw bytes buffer (dynamically readjusted)
-        size_t capacity_;  // Capacity of the buffer
-        size_t index_;     // Read/write head position
+        string buf_ = string(DEFAULT_RPC_SZ, 0); // Raw bytes buffer
+        size_t index_ = RPC_HEADER_SZ; // Read/write head position
 
         inline void reserve(size_t n) {
-            if((index_+n) > capacity_){
-                capacity_ += std::max(capacity_, n);
-                VERIFY (buf_ != NULL);
-                buf_ = (char *)realloc(buf_, capacity_);
-                VERIFY(buf_);
-            }
+            if (index_+n > buf_.size())
+                buf_.resize(index_+n);
         }
     public:
-        struct pass { template <typename... Args> inline pass(Args&&...) {} };
-
         template <typename... Args>
-
         marshall(const Args&... args) {
-            buf_ = (char *) malloc(sizeof(char)*DEFAULT_RPC_SZ);
-            VERIFY(buf_);
-            capacity_ = DEFAULT_RPC_SZ;
-            index_ = RPC_HEADER_SZ;
             (void)pass{(*this << args)...};
         }
 
-        ~marshall() {
-            if (buf_)
-                free(buf_);
-        }
-
-        size_t size() { return index_;}
-        char *cstr() { return buf_;}
-        const char *cstr() const { return buf_;}
-
-        void rawbyte(uint8_t x) {
-            reserve(1);
-            buf_[index_++] = (int8_t)x;
-        }
-
-        void rawbytes(const char *p, size_t n) {
+        void rawbytes(const void *p, size_t n) {
             reserve(n);
-            memcpy(buf_+index_, p, n);
+            copy((char *)p, (char *)p+n, &buf_[index_]);
             index_ += n;
         }
 
-        // Return the current content (excluding header) as a string
-        std::string get_content() {
-            return std::string(buf_+RPC_HEADER_SZ,index_-RPC_HEADER_SZ);
-        }
-
-        // Return the current content (excluding header) as a string
-        std::string str() {
-            return get_content();
-        }
-
-        void pack_req_header(const request_header &h);
-        void pack_reply_header(const reply_header &h);
-
-        void take_buf(char **b, size_t *s) {
-            *b = buf_;
-            *s = index_;
-            buf_ = NULL;
-            index_ = 0;
-            return;
+        // with header
+        operator string () const { return buf_.substr(0,index_); }
+        // without header
+        string content() { return buf_.substr(RPC_HEADER_SZ,index_-RPC_HEADER_SZ); }
+
+        template <class T>
+        void pack_header(const T &h) {
+            VERIFY(sizeof(T)+sizeof(rpc_sz_t) <= RPC_HEADER_SZ);
+            size_t saved_sz = index_;
+            index_ = sizeof(rpc_sz_t); // first 4 bytes hold length field
+            *this << h;
+            index_ = saved_sz;
         }
 };
 
-marshall& operator<<(marshall &, bool);
-marshall& operator<<(marshall &, uint32_t);
-marshall& operator<<(marshall &, int32_t);
-marshall& operator<<(marshall &, uint8_t);
-marshall& operator<<(marshall &, int8_t);
-marshall& operator<<(marshall &, uint16_t);
-marshall& operator<<(marshall &, int16_t);
-marshall& operator<<(marshall &, uint64_t);
-marshall& operator<<(marshall &, const std::string &);
-
-template <class A, typename I=void>
-struct is_enumerable : std::false_type {};
-
-template<class A> struct is_enumerable<A,
-    decltype(std::declval<A&>().cbegin(), std::declval<A&>().cend(), void())
-> : std::true_type {};
-
-template <class A> typename std::enable_if<is_enumerable<A>::value, marshall>::type &
+FORWARD_MARSHALLABLE(bool);
+FORWARD_MARSHALLABLE(uint8_t);
+FORWARD_MARSHALLABLE(int8_t);
+FORWARD_MARSHALLABLE(uint16_t);
+FORWARD_MARSHALLABLE(int16_t);
+FORWARD_MARSHALLABLE(uint32_t);
+FORWARD_MARSHALLABLE(int32_t);
+FORWARD_MARSHALLABLE(size_t);
+FORWARD_MARSHALLABLE(uint64_t);
+FORWARD_MARSHALLABLE(int64_t);
+FORWARD_MARSHALLABLE(string &);
+
+template <class A> typename enable_if<is_iterable<A>::value, marshall>::type &
 operator<<(marshall &m, const A &x) {
-    m << (unsigned int) x.size();
+    m << (unsigned int)x.size();
     for (const auto &a : x)
         m << a;
     return m;
 }
 
 template <class A, class B> marshall &
-operator<<(marshall &m, const std::pair<A,B> &d) {
+operator<<(marshall &m, const pair<A,B> &d) {
     return m << d.first << d.second;
 }
 
 template<typename E>
-using enum_type_t = typename std::enable_if<std::is_enum<E>::value, typename std::underlying_type<E>::type>::type;
+using enum_type_t = typename enable_if<is_enum<E>::value, typename underlying_type<E>::type>::type;
 template<typename E> constexpr inline enum_type_t<E> from_enum(E e) noexcept { return (enum_type_t<E>)e; }
 template<typename E> constexpr inline E to_enum(enum_type_t<E> value) noexcept { return (E)value; }
 
-template <class E> typename std::enable_if<std::is_enum<E>::value, marshall>::type &
+template <class E> typename enable_if<is_enum<E>::value, marshall>::type &
 operator<<(marshall &m, E e) {
     return m << from_enum(e);
 }
 
-class unmarshall;
-
-unmarshall& operator>>(unmarshall &, bool &);
-unmarshall& operator>>(unmarshall &, uint8_t &);
-unmarshall& operator>>(unmarshall &, int8_t &);
-unmarshall& operator>>(unmarshall &, uint16_t &);
-unmarshall& operator>>(unmarshall &, int16_t &);
-unmarshall& operator>>(unmarshall &, uint32_t &);
-unmarshall& operator>>(unmarshall &, int32_t &);
-unmarshall& operator>>(unmarshall &, size_t &);
-unmarshall& operator>>(unmarshall &, uint64_t &);
-unmarshall& operator>>(unmarshall &, int64_t &);
-unmarshall& operator>>(unmarshall &, std::string &);
-template <class E> typename std::enable_if<std::is_enum<E>::value, unmarshall>::type &
+template <class E> typename enable_if<is_enum<E>::value, unmarshall>::type &
 operator>>(unmarshall &u, E &e);
 
 class unmarshall {
     private:
-        char *buf_;
-        size_t sz_;
-        size_t index_;
-        bool ok_;
-
-        inline bool ensure(size_t n);
-    public:
-        unmarshall(): buf_(NULL),sz_(0),index_(0),ok_(false) {}
-        unmarshall(char *b, size_t sz): buf_(b),sz_(sz),index_(),ok_(true) {}
-        unmarshall(const std::string &s) : buf_(NULL),sz_(0),index_(0),ok_(false)
-        {
-            //take the content which does not exclude a RPC header from a string
-            take_content(s);
-        }
-        ~unmarshall() {
-            if (buf_) free(buf_);
+        string buf_;
+        size_t index_ = 0;
+        bool ok_ = false;
+
+        inline bool ensure(size_t n) {
+            if (index_+n > buf_.size())
+                ok_ = false;
+            return ok_;
         }
-
-        //take contents from another unmarshall object
-        void take_in(unmarshall &another);
-
-        //take the content which does not exclude a RPC header from a string
-        void take_content(const std::string &s) {
-            sz_ = s.size()+RPC_HEADER_SZ;
-            buf_ = (char *)realloc(buf_,sz_);
-            VERIFY(buf_);
-            index_ = RPC_HEADER_SZ;
-            memcpy(buf_+index_, s.data(), s.size());
-            ok_ = true;
+    public:
+        unmarshall() {}
+        unmarshall(const string &s, bool has_header)
+            : buf_(s),index_(RPC_HEADER_SZ) {
+            if (!has_header)
+                buf_.insert(0, RPC_HEADER_SZ, 0);
+            ok_ = (buf_.size() >= RPC_HEADER_SZ);
         }
 
         bool ok() const { return ok_; }
-        char *cstr() { return buf_;}
-        bool okdone() const { return ok_ && index_ == sz_; }
-
-        uint8_t rawbyte();
-        void rawbytes(std::string &s, size_t n);
-        template <class T> void rawbytes(T &t);
-
-        size_t ind() { return index_;}
-        size_t size() { return sz_;}
-        void take_buf(char **b, size_t *sz) {
-            *b = buf_;
-            *sz = sz_;
-            sz_ = index_ = 0;
-            buf_ = NULL;
-        }
+        bool okdone() const { return ok_ && index_ == buf_.size(); }
 
-        void unpack_req_header(request_header *h) {
-            //the first 4-byte is for channel to fill size of pdu
-            index_ = sizeof(rpc_sz_t);
-            *this >> h->xid >> h->proc >> h->clt_nonce >> h->srv_nonce >> h->xid_rep;
-            index_ = RPC_HEADER_SZ;
+        void rawbytes(void * t, size_t n) {
+            VERIFY(ensure(n));
+            copy(&buf_[index_], &buf_[index_+n], (char *)t);
+            index_ += n;
         }
 
-        void unpack_reply_header(reply_header *h) {
-            //the first 4-byte is for channel to fill size of pdu
+        template <class T>
+        void unpack_header(T & h) {
+            // first 4 bytes hold length field
+            VERIFY(sizeof(T)+sizeof(rpc_sz_t) <= RPC_HEADER_SZ);
             index_ = sizeof(rpc_sz_t);
-            *this >> h->xid >> h->ret;
+            *this >> h;
             index_ = RPC_HEADER_SZ;
         }
 
-        template <class A>
-        inline A grab() {
-            A a;
-            *this >> a;
-            return a;
-        }
+        template <class T> inline T grab() { T t; *this >> t; return t; }
 };
 
-template <class A> typename std::enable_if<is_enumerable<A>::value, unmarshall>::type &
+template <class A> typename enable_if<is_iterable<A>::value, unmarshall>::type &
 operator>>(unmarshall &u, A &x) {
     unsigned n = u.grab<unsigned>();
     x.clear();
@@ -265,26 +181,26 @@ operator>>(unmarshall &u, A &x) {
 }
 
 template <class A, class B> unmarshall &
-operator>>(unmarshall &u, std::map<A,B> &x) {
+operator>>(unmarshall &u, map<A,B> &x) {
     unsigned n = u.grab<unsigned>();
     x.clear();
     while (n--)
-        x.emplace(u.grab<std::pair<A,B>>());
+        x.emplace(u.grab<pair<A,B>>());
     return u;
 }
 
 template <class A, class B> unmarshall &
-operator>>(unmarshall &u, std::pair<A,B> &d) {
+operator>>(unmarshall &u, pair<A,B> &d) {
     return u >> d.first >> d.second;
 }
 
-template <class E> typename std::enable_if<std::is_enum<E>::value, unmarshall>::type &
+template <class E> typename enable_if<is_enum<E>::value, unmarshall>::type &
 operator>>(unmarshall &u, E &e) {
     e = to_enum<E>(u.grab<enum_type_t<E>>());
     return u;
 }
 
-typedef std::function<int(unmarshall &, marshall &)> handler;
+typedef function<int(unmarshall &, marshall &)> handler;
 
 //
 // Automatic marshalling wrappers for RPC handlers
@@ -293,8 +209,8 @@ typedef std::function<int(unmarshall &, marshall &)> handler;
 // PAI 2013/09/19
 // C++11 does neither of these two things for us:
 // 1) Declare variables using a parameter pack expansion, like so
-//      Args ...args;
-// 2) Call a function with a std::tuple of the arguments it expects
+//      Args... args;
+// 2) Call a function with a tuple of the arguments it expects
 //
 // We implement an 'invoke' function for functions of the RPC handler
 // signature, i.e. int(R & r, const Args...)
@@ -307,21 +223,6 @@ typedef std::function<int(unmarshall &, marshall &)> handler;
 // 'invoke' as a parameter which will be ignored, but its type will force the
 // compiler to specialize 'invoke' appropriately.
 
-// The following implementation of tuple_indices is redistributed under the MIT
-// License as an insubstantial portion of the LLVM compiler infrastructure.
-
-template <size_t...> struct tuple_indices {};
-template <size_t S, class IntTuple, size_t E> struct make_indices_imp;
-template <size_t S, size_t ...Indices, size_t E> struct make_indices_imp<S, tuple_indices<Indices...>, E> {
-    typedef typename make_indices_imp<S+1, tuple_indices<Indices..., S>, E>::type type;
-};
-template <size_t E, size_t ...Indices> struct make_indices_imp<E, tuple_indices<Indices...>, E> {
-    typedef tuple_indices<Indices...> type;
-};
-template <size_t E, size_t S=0> struct make_tuple_indices {
-    typedef typename make_indices_imp<S, tuple_indices<>, E>::type type;
-};
-
 // This class encapsulates the default response to runtime unmarshalling
 // failures.  The templated wrappers below may optionally use a different
 // class.
@@ -338,18 +239,18 @@ struct VerifyOnFailure {
 
 // One for function pointers...
 
-template <class F, class R, class RV, class args_type, size_t ...Indices>
-typename std::enable_if<!std::is_member_function_pointer<F>::value, RV>::type
+template <class F, class R, class RV, class args_type, size_t... Indices>
+typename enable_if<!is_member_function_pointer<F>::value, RV>::type
 invoke(RV, F f, void *, R & r, args_type & t, tuple_indices<Indices...>) {
-    return f(r, std::move(std::get<Indices>(t))...);
+    return f(r, move(get<Indices>(t))...);
 }
 
 // And one for pointers to member functions...
 
-template <class F, class C, class RV, class R, class args_type, size_t ...Indices>
-typename std::enable_if<std::is_member_function_pointer<F>::value, RV>::type
+template <class F, class C, class RV, class R, class args_type, size_t... Indices>
+typename enable_if<is_member_function_pointer<F>::value, RV>::type
 invoke(RV, F f, C *c, R & r, args_type & t, tuple_indices<Indices...>) {
-    return (c->*f)(r, std::move(std::get<Indices>(t))...);
+    return (c->*f)(r, move(get<Indices>(t))...);
 }
 
 // The class marshalled_func_imp uses partial template specialization to
@@ -373,15 +274,15 @@ struct marshalled_func_imp<F, C, RV(R&, Args...), ErrorHandler> {
         // template parameters running from 0 up to (# args) - 1.
         using Indices = typename make_tuple_indices<sizeof...(Args)>::type;
         // This type definition represents storage for f's unmarshalled
-        // arguments.  std::decay is (most notably) stripping off const
+        // arguments.  decay is (most notably) stripping off const
         // qualifiers.
-        using ArgsStorage = std::tuple<typename std::decay<Args>::type...>;
-        // Allocate a handler (i.e. std::function) to hold the lambda
+        using ArgsStorage = tuple<typename decay<Args>::type...>;
+        // Allocate a handler (i.e. function) to hold the lambda
         // which will unmarshall RPCs and call f.
         return new handler([=](unmarshall &u, marshall &m) -> RV {
             // Unmarshall each argument with the correct type and store the
             // result in a tuple.
-            ArgsStorage t = {u.grab<typename std::decay<Args>::type>()...};
+            ArgsStorage t = {u.grab<typename decay<Args>::type>()...};
             // Verify successful unmarshalling of the entire input stream.
             if (!u.okdone())
                 return (RV)ErrorHandler::unmarshall_args_failure();
@@ -417,7 +318,34 @@ struct marshalled_func<F, ErrorHandler, RV(C::*)(Args...)> :
     public marshalled_func_imp<F, C, RV(Args...), ErrorHandler> {};
 
 template <class F, class ErrorHandler, class Signature>
-struct marshalled_func<F, ErrorHandler, std::function<Signature>> :
+struct marshalled_func<F, ErrorHandler, function<Signature>> :
     public marshalled_func_imp<F, void, Signature, ErrorHandler> {};
 
+template <class... Args, size_t... Indices> unmarshall &
+tuple_unmarshall_imp(unmarshall & u, tuple<Args &...> t, tuple_indices<Indices...>) {
+    (void)pass{(u >> get<Indices>(t))...};
+    return u;
+}
+
+template <class... Args> unmarshall &
+operator>>(unmarshall & u, tuple<Args &...> && t) {
+    using Indices = typename make_tuple_indices<sizeof...(Args)>::type;
+    return tuple_unmarshall_imp(u, t, Indices());
+}
+
+template <class... Args, size_t... Indices> marshall &
+tuple_marshall_imp(marshall & m, tuple<Args...> & t, tuple_indices<Indices...>) {
+    (void)pass{(m << get<Indices>(t))...};
+    return m;
+}
+
+template <class... Args> marshall &
+operator<<(marshall & m, tuple<Args...> && t) {
+    using Indices = typename make_tuple_indices<sizeof...(Args)>::type;
+    return tuple_marshall_imp(m, t, Indices());
+}
+
+MARSHALLABLE(request_header)
+MARSHALLABLE(reply_header)
+
 #endif