lib9p_srv: Require less compile-time config

6 files changed, 61 insertions, 77 deletions

diff --git a/build-aux/measurestack/app_plugins.py b/build-aux/measurestack/app_plugins.py
index 9152ef3..bbb0eae 100644
--- a/build-aux/measurestack/app_plugins.py
+++ b/build-aux/measurestack/app_plugins.py
@@ -4,6 +4,7 @@
 # SPDX-License-Identifier: AGPL-3.0-or-later
 
 import re
+import subprocess
 import typing
 
 from . import analyze, util
@@ -271,9 +272,8 @@ re_lib9p_callee = re.compile(
 class Lib9PPlugin:
     tmessage_handlers: set[QName] | None
     lib9p_msgs: set[str]
-    _CONFIG_9P_NUM_SOCKS: int | None
-    CONFIG_9P_SRV_MAX_REQS: int | None
-    CONFIG_9P_SRV_MAX_DEPTH: int | None
+    _CONFIG_9P_MAX_CONNS: int | None
+    _CONFIG_9P_MAX_REQS: int | None
     formatters: typing.Collection[BaseName]
 
     def __init__(
@@ -312,18 +312,18 @@ class Lib9PPlugin:
 
         def config_h_get(varname: str) -> int | None:
             if config_h_fname:
-                with open(config_h_fname, "r", encoding="utf-8") as fh:
-                    for line in fh:
-                        line = line.rstrip()
-                        if line.startswith("#define"):
-                            parts = line.split()
-                            if parts[1] == varname:
-                                return int(parts[2])
+                line = subprocess.run(
+                    ["cpp"],
+                    input=f'#include "{config_h_fname}"\n{varname}\n',
+                    check=True,
+                    capture_output=True,
+                    encoding="utf-8",
+                ).stdout.split("\n")[-2]
+                return int(eval(line))  # pylint: disable=eval-used
             return None
 
-        self._CONFIG_9P_NUM_SOCKS = config_h_get("_CONFIG_9P_NUM_SOCKS")
-        self.CONFIG_9P_SRV_MAX_REQS = config_h_get("CONFIG_9P_SRV_MAX_REQS")
-        self.CONFIG_9P_SRV_MAX_DEPTH = config_h_get("CONFIG_9P_SRV_MAX_DEPTH")
+        self._CONFIG_9P_MAX_CONNS = config_h_get("_CONFIG_9P_MAX_REQS")
+        self._CONFIG_9P_MAX_REQS = config_h_get("_CONFIG_9P_MAX_REQS")
 
         # Read sources #########################################################
 
@@ -348,12 +348,12 @@ class Lib9PPlugin:
         self.lib9p_msgs = lib9p_msgs
 
     def thread_count(self, name: QName) -> int:
-        assert self._CONFIG_9P_NUM_SOCKS
-        assert self.CONFIG_9P_SRV_MAX_REQS
+        assert self._CONFIG_9P_MAX_CONNS
+        assert self._CONFIG_9P_MAX_REQS
         if "read" in str(name.base()):
-            return self._CONFIG_9P_NUM_SOCKS
+            return self._CONFIG_9P_MAX_CONNS
         if "write" in str(name.base()):
-            return self._CONFIG_9P_NUM_SOCKS * self.CONFIG_9P_SRV_MAX_REQS
+            return self._CONFIG_9P_MAX_REQS
         return 1
 
     def is_intrhandler(self, name: QName) -> bool:
@@ -405,11 +405,6 @@ class Lib9PPlugin:
                 self.formatters, self._skipmodel__vfctprintf
             ),
         }
-        if isinstance(self.CONFIG_9P_SRV_MAX_DEPTH, int):
-            ret[BaseName("srv_path_decref")] = analyze.SkipModel(
-                self.CONFIG_9P_SRV_MAX_DEPTH,
-                self._skipmodel_srv_path_decref,
-            )
         return ret
 
     def _skipmodel__lib9p_validate_unmarshal_marshal(
@@ -423,17 +418,6 @@ class Lib9PPlugin:
             return False
         return m_caller.group("grp") != m_callee.group("grp")
 
-    def _skipmodel_srv_path_decref(
-        self, chain: typing.Sequence[QName], call: QName
-    ) -> bool:
-        assert isinstance(self.CONFIG_9P_SRV_MAX_DEPTH, int)
-        if call.base() == BaseName("srv_path_decref"):
-            return len(chain) >= self.CONFIG_9P_SRV_MAX_DEPTH and all(
-                c.base() == BaseName("srv_path_decref")
-                for c in chain[-self.CONFIG_9P_SRV_MAX_DEPTH :]
-            )
-        return False
-
     def _skipmodel__vfctprintf(
         self, chain: typing.Sequence[QName], call: QName
     ) -> bool:
diff --git a/cmd/sbc_harness/config/config.h b/cmd/sbc_harness/config/config.h
index 14c2f03..5367dbe 100644
--- a/cmd/sbc_harness/config/config.h
+++ b/cmd/sbc_harness/config/config.h
@@ -11,6 +11,9 @@
 
 #define CONFIG_FLASH_DEBUG 1
 
+#define _CONFIG_9P_MAX_CONNS    3 /* FIXME: bump this back up to 8 */
+#define _CONFIG_9P_MAX_REQS     (2*_CONFIG_9P_MAX_CONNS)
+
 /* RP2040 *********************************************************************/
 
 #define CONFIG_RP2040_SPI_DEBUG         1 /* bool */
@@ -60,9 +63,6 @@
  * struct padding, (2) array pointers.
  */
 #define CONFIG_9P_SRV_MAX_HOSTMSG_SIZE  CONFIG_9P_SRV_MAX_MSG_SIZE+16
-#define CONFIG_9P_SRV_MAX_FIDS          16
-#define CONFIG_9P_SRV_MAX_REQS          2
-#define CONFIG_9P_SRV_MAX_DEPTH         3
 
 #define CONFIG_9P_ENABLE_9P2000         1 /* bool */
 #define CONFIG_9P_ENABLE_9P2000_u       1 /* bool */
@@ -104,12 +104,11 @@ extern const size_t CONFIG_COROUTINE_STACK_SIZE_w5500_irq_cr;
 #define CONFIG_COROUTINE_VALGRIND              0 /* bool */
 #define CONFIG_COROUTINE_GDB                   1 /* bool */
 
-#define _CONFIG_9P_NUM_SOCKS                   3 /* FIXME: bump this back up to 8 */
-#define CONFIG_COROUTINE_NUM                   (                                 \
-	1                                             /* usb_common         */ + \
-	1                                             /* usb_keyboard       */ + \
-	1                                             /* W5500 irq handler  */ + \
-	_CONFIG_9P_NUM_SOCKS                          /* 9P accept()+read() */ + \
-	(CONFIG_9P_SRV_MAX_REQS*_CONFIG_9P_NUM_SOCKS) /* 9P work+write()    */ )
+#define CONFIG_COROUTINE_NUM                   (        \
+	1                    /* usb_common         */ + \
+	1                    /* usb_keyboard       */ + \
+	1                    /* W5500 irq handler  */ + \
+	_CONFIG_9P_MAX_CONNS /* 9P accept()+read() */ + \
+	_CONFIG_9P_MAX_REQS  /* 9P work+write()    */ )
 
 #endif /* _CONFIG_H_ */
diff --git a/cmd/sbc_harness/main.c b/cmd/sbc_harness/main.c
index 20cf5b1..5630e83 100644
--- a/cmd/sbc_harness/main.c
+++ b/cmd/sbc_harness/main.c
@@ -39,6 +39,13 @@
 
 #include "config.h"
 
+#ifndef _CONFIG_9P_MAX_CONNS
+	#error config.h must define _CONFIG_9P_MAX_CONNS
+#endif
+#ifndef _CONFIG_9P_MAX_REQS
+	#error config.h must define _CONFIG_9P_MAX_REQS
+#endif
+
 /* file tree ******************************************************************/
 
 enum { PATH_BASE = __COUNTER__ };
@@ -167,7 +174,7 @@ static COROUTINE write9p_cr(void *) {
 }
 
 const char *const hexdig = "0123456789ABCDEF";
-static_assert(CONFIG_9P_SRV_MAX_REQS*_CONFIG_9P_NUM_SOCKS <= 16);
+static_assert(_CONFIG_9P_MAX_REQS <= 16);
 
 COROUTINE init_cr(void *) {
 	cr_begin();
@@ -223,11 +230,11 @@ COROUTINE init_cr(void *) {
 	coroutine_add("usb_keyboard", usb_keyboard_cr, &globals.keyboard_chan);
 	//coroutine_add("hello_world", hello_world_cr, &globals.keyboard_chan);
 	coroutine_add("dhcp", dhcp_cr, NULL);
-	for (int i = 0; i < _CONFIG_9P_NUM_SOCKS; i++) {
+	for (int i = 0; i < _CONFIG_9P_MAX_CONNS; i++) {
 		char name[] = {'r', 'e', 'a', 'd', '-', hexdig[i], '\0'};
 		coroutine_add(name, read9p_cr, NULL);
 	}
-	for (int i = 0; i < CONFIG_9P_SRV_MAX_REQS*_CONFIG_9P_NUM_SOCKS; i++) {
+	for (int i = 0; i < _CONFIG_9P_MAX_REQS; i++) {
 		char name[] = {'w', 'r', 'i', 't', 'e', '-', hexdig[i], '\0'};
 		coroutine_add(name, write9p_cr, NULL);
 	}
diff --git a/lib9p/srv.c b/lib9p/srv.c
index c64f995..e664d0f 100644
--- a/lib9p/srv.c
+++ b/lib9p/srv.c
@@ -32,16 +32,6 @@
 
 #include "config.h"
 
-#ifndef CONFIG_9P_SRV_MAX_FIDS
-	#error config.h must define CONFIG_9P_SRV_MAX_FIDS
-#endif
-#ifndef CONFIG_9P_SRV_MAX_REQS
-	#error config.h must define CONFIG_9P_SRV_MAX_REQS
-#endif
-#ifndef CONFIG_9P_SRV_MAX_DEPTH
-	/* 1=just the root dir, 2=just files in the root dir, 3=1 subdir, ... */
-	#error config.h must define CONFIG_9P_SRV_MAX_DEPTH
-#endif
 #ifndef CONFIG_9P_SRV_MAX_MSG_SIZE
 	#error config.h must define CONFIG_9P_SRV_MAX_MSG_SIZE
 #endif
@@ -249,14 +239,18 @@ static inline struct srv_pathinfo *srv_path_save(struct srv_req *ctx,
 static inline void srv_path_decref(struct srv_req *ctx, srv_path_t path) {
 	assert(ctx);
 
-	struct srv_pathinfo *pathinfo = map_load(&ctx->parent_sess->paths, path);
-	assert(pathinfo);
-	pathinfo->gc_refcount--;
-	if (pathinfo->gc_refcount == 0) {
-		if (pathinfo->parent_dir != path)
-			srv_path_decref(ctx, pathinfo->parent_dir);
+	for (;;) {
+		struct srv_pathinfo *pathinfo = map_load(&ctx->parent_sess->paths, path);
+		assert(pathinfo);
+		pathinfo->gc_refcount--;
+		if (pathinfo->gc_refcount)
+			break;
+		srv_path_t parent_path = pathinfo->parent_dir;
 		LO_CALL(pathinfo->file, free);
 		map_del(&ctx->parent_sess->paths, path);
+		if (parent_path == path)
+			break;
+		path = parent_path;
 	}
 }
 
diff --git a/lib9p/tests/test_server/config/config.h b/lib9p/tests/test_server/config/config.h
index 03143e1..d9cf008 100644
--- a/lib9p/tests/test_server/config/config.h
+++ b/lib9p/tests/test_server/config/config.h
@@ -7,8 +7,8 @@
 #ifndef _CONFIG_H_
 #define _CONFIG_H_
 
-#define _CONFIG_9P_NUM_SOCKS          8
-#define CONFIG_SRV9P_NUM_CONNS        _CONFIG_9P_NUM_SOCKS
+#define _CONFIG_9P_MAX_CONNS    8
+#define _CONFIG_9P_MAX_REQS     (2*_CONFIG_9P_MAX_CONNS)
 
 /* 9P *************************************************************************/
 
@@ -38,9 +38,6 @@
  * struct padding, (2) array pointers.
  */
 #define CONFIG_9P_SRV_MAX_HOSTMSG_SIZE  CONFIG_9P_SRV_MAX_MSG_SIZE+16
-#define CONFIG_9P_SRV_MAX_FIDS          16
-#define CONFIG_9P_SRV_MAX_REQS          2
-#define CONFIG_9P_SRV_MAX_DEPTH         3
 
 #define CONFIG_9P_ENABLE_9P2000         1 /* bool */
 #define CONFIG_9P_ENABLE_9P2000_u       1 /* bool */
@@ -57,10 +54,10 @@
 #define CONFIG_COROUTINE_DEBUG                 0 /* bool */
 #define CONFIG_COROUTINE_VALGRIND              1 /* bool */
 #define CONFIG_COROUTINE_GDB                   1 /* bool */
-#define CONFIG_COROUTINE_NUM                   (                             \
-	1                                               /* usb_common   */ + \
-	1                                               /* usb_keyboard */ + \
-	CONFIG_SRV9P_NUM_CONNS                          /* accept+read  */ + \
-	(CONFIG_9P_SRV_MAX_REQS*CONFIG_SRV9P_NUM_CONNS) /* work+write   */ )
+#define CONFIG_COROUTINE_NUM                   (  \
+	1                    /* usb_common   */ + \
+	1                    /* usb_keyboard */ + \
+	_CONFIG_9P_MAX_CONNS /* accept+read  */ + \
+	_CONFIG_9P_MAX_REQS  /* work+write   */ )
 
 #endif /* _CONFIG_H_ */
diff --git a/lib9p/tests/test_server/main.c b/lib9p/tests/test_server/main.c
index f89166f..0705747 100644
--- a/lib9p/tests/test_server/main.c
+++ b/lib9p/tests/test_server/main.c
@@ -27,8 +27,11 @@
 
 #include "config.h"
 
-#ifndef CONFIG_SRV9P_NUM_CONNS
-	#error config.h must define CONFIG_SRV9P_NUM_CONNS
+#ifndef _CONFIG_9P_MAX_CONNS
+	#error config.h must define _CONFIG_9P_MAX_CONNS
+#endif
+#ifndef _CONFIG_9P_MAX_REQS
+	#error config.h must define _CONFIG_9P_MAX_REQS
 #endif
 
 /* globals ********************************************************************/
@@ -39,7 +42,7 @@ const char *hexdig = "0123456789abcdef";
 
 struct {
 	uint16_t                        port;
-	struct hostnet_tcp_listener     listeners[CONFIG_SRV9P_NUM_CONNS];
+	struct hostnet_tcp_listener     listeners[_CONFIG_9P_MAX_CONNS];
 	struct lib9p_srv                srv;
 	FILE                           *logstream;
 } globals = {
@@ -110,12 +113,12 @@ static COROUTINE init_cr(void *) {
 
 	sleep_for_ms(1); /* test that sleep works */
 
-	for (int i = 0; i < CONFIG_SRV9P_NUM_CONNS; i++) {
+	for (int i = 0; i < _CONFIG_9P_MAX_CONNS; i++) {
 		char name[] = {'r', 'e', 'a', 'd', '-', hexdig[i], '\0'};
 		if (!coroutine_add(name, read_cr, &i))
 			error(1, 0, "coroutine_add(read_cr, &i)");
 	}
-	for (int i = 0; i < 2*CONFIG_SRV9P_NUM_CONNS; i++) {
+	for (int i = 0; i < _CONFIG_9P_MAX_REQS; i++) {
 		char name[] = {'w', 'r', 'i', 't', 'e', '-', hexdig[i], '\0'};
 		if (!coroutine_add(name, write_cr, NULL))
 			error(1, 0, "coroutine_add(write_cr, NULL)");