Style fixes in TCP code; remove MIN and PAIR from util.h.

* Moved PAIR to toxav, where it's used (but really this should die).
* Replace most MIN calls with typed `min_*` calls. Didn't replace the
  ones where the desired semantics are unclear. Moved the MIN macro to
  the one place where it's still used.
* Avoid assignments in `while` loops. Instead, factored out the loop body
  into a separate `bool`-returning function.
* Use named types for callbacks (`_cb` types).
* Avoid assignments in `if` conditions.
* Removed `MAKE_REALLOC` and expanded its two calls. We can't have
  templates in C, and this fake templating is ugly and hard to analyse
  and debug (it expands on a single line).
* Moved epoll system include to the .c file, out of the .h file.
* Avoid assignments in expressions (`a = b = c;`).
* Avoid multiple declarators per struct member declaration.
* Fix naming inconsistencies.
* Replace `net_to_host` macro with function.

CMakeLists.txt

@@ -261,6 +261,7 @@ if(BUILD_TOXAV)
     toxav/groupav.h
     toxav/msi.c
     toxav/msi.h
+    toxav/pair.h
     toxav/ring_buffer.c
     toxav/ring_buffer.h
     toxav/rtp.c

auto_tests/file_transfer_test.c

@@ -286,7 +286,7 @@ static void file_transfer_test(void)
             printf("after %u iterations: %.2fMiB done\n", (unsigned int)i + 1, (double)size_recv / 1024 / 1024);
         }
 
-        c_sleep(MIN(tox1_interval, MIN(tox2_interval, tox3_interval)));
+        c_sleep(min_u32(tox1_interval, min_u32(tox2_interval, tox3_interval)));
     }
 
     ck_assert_msg(file_sending_done, "file sending did not complete after %u iterations: sendf_ok:%u file_recv:%u "
@@ -348,7 +348,7 @@ static void file_transfer_test(void)
         uint32_t tox2_interval = tox_iteration_interval(tox2);
         uint32_t tox3_interval = tox_iteration_interval(tox3);
 
-        c_sleep(MIN(tox1_interval, MIN(tox2_interval, tox3_interval)));
+        c_sleep(min_u32(tox1_interval, min_u32(tox2_interval, tox3_interval)));
     }
 
     printf("Starting file 0 transfer test.\n");
@@ -397,7 +397,7 @@ static void file_transfer_test(void)
         uint32_t tox2_interval = tox_iteration_interval(tox2);
         uint32_t tox3_interval = tox_iteration_interval(tox3);
 
-        c_sleep(MIN(tox1_interval, MIN(tox2_interval, tox3_interval)));
+        c_sleep(min_u32(tox1_interval, min_u32(tox2_interval, tox3_interval)));
     }
 
     printf("file_transfer_test succeeded, took %llu seconds\n", time(nullptr) - cur_time);

toxav/BUILD.bazel

@@ -54,11 +54,17 @@ cc_test(
     ],
 )
 
+cc_library(
+    name = "pair",
+    hdrs = ["pair.h"],
+)
+
 cc_library(
     name = "audio",
     srcs = ["audio.c"],
     hdrs = ["audio.h"],
     deps = [
+        ":pair",
         ":public",
         ":rtp",
         "//c-toxcore/toxcore:network",
@@ -78,6 +84,7 @@ cc_library(
     ],
     deps = [
         ":audio",
+        ":pair",
         ":public",
         "//c-toxcore/toxcore:network",
         "@libvpx",

toxav/Makefile.inc

@@ -16,6 +16,7 @@ libtoxav_la_SOURCES = ../toxav/rtp.h \
                     ../toxav/video.c \
                     ../toxav/bwcontroller.h \
                     ../toxav/bwcontroller.c \
+                    ../toxav/pair.h \
                     ../toxav/ring_buffer.h \
                     ../toxav/ring_buffer.c \
                     ../toxav/toxav.h \

toxav/audio.h

@@ -24,6 +24,7 @@
 
 #include "../toxcore/logger.h"
 #include "../toxcore/util.h"
+#include "pair.h"
 
 #include <opus.h>
 #include <pthread.h>

toxav/pair.h

@@ -0,0 +1,6 @@
+#ifndef C_TOXCORE_TOXAV_PAIR_H
+#define C_TOXCORE_TOXAV_PAIR_H
+
+#define PAIR(TYPE1__, TYPE2__) struct { TYPE1__ first; TYPE2__ second; }
+
+#endif // C_TOXCORE_TOXAV_PAIR_H

toxav/toxav.c

@@ -242,6 +242,10 @@ void toxav_iterate(ToxAV *av)
             ac_iterate(i->audio.second);
             vc_iterate(i->video.second);
 
+            // TODO(iphydf): Find out what MIN-semantics are desired here and
+            // use a min_* function from util.h.
+#define MIN(a,b) (((a)<(b))?(a):(b))
+
             if (i->msi_call->self_capabilities & msi_CapRAudio &&
                     i->msi_call->peer_capabilities & msi_CapSAudio) {
                 rc = MIN(i->audio.second->lp_frame_duration, rc);

toxav/video.h

@@ -24,6 +24,7 @@
 
 #include "../toxcore/logger.h"
 #include "../toxcore/util.h"
+#include "pair.h"
 
 #include <vpx/vpx_decoder.h>
 #include <vpx/vpx_encoder.h>

toxcore/Messenger.c

@@ -717,7 +717,9 @@ int m_copy_statusmessage(const Messenger *m, int32_t friendnumber, uint8_t *buf,
         return -1;
     }
 
-    int msglen = MIN(maxlen, m->friendlist[friendnumber].statusmessage_length);
+    // TODO(iphydf): This should be uint16_t and min_u16. If maxlen exceeds
+    // uint16_t's range, it won't affect the result.
+    uint32_t msglen = min_u32(maxlen, m->friendlist[friendnumber].statusmessage_length);
 
     memcpy(buf, m->friendlist[friendnumber].statusmessage, msglen);
     memset(buf + msglen, 0, maxlen - msglen);
@@ -2855,9 +2857,10 @@ static uint32_t friends_list_save(const Messenger *m, uint8_t *data)
             memcpy(temp.real_pk, m->friendlist[i].real_pk, CRYPTO_PUBLIC_KEY_SIZE);
 
             if (temp.status < 3) {
+                // TODO(iphydf): Use uint16_t and min_u16 here.
                 const size_t friendrequest_length =
-                    MIN(m->friendlist[i].info_size,
-                        MIN(SAVED_FRIEND_REQUEST_SIZE, MAX_FRIEND_REQUEST_DATA_SIZE));
+                    min_u32(m->friendlist[i].info_size,
+                            min_u32(SAVED_FRIEND_REQUEST_SIZE, MAX_FRIEND_REQUEST_DATA_SIZE));
                 memcpy(temp.info, m->friendlist[i].info, friendrequest_length);
 
                 temp.info_size = net_htons(m->friendlist[i].info_size);