[PATCH 13/13] qrap: Run static checkers

[David Gibson <david@gibson.dropbear.id.au>]

Run the static checkers on qrap as well as on passt-repair and passt.  This
shows a number of minor warnings, which we fix.

Signed-off-by: David Gibson <david@gibson.dropbear.id.au>
---
 Makefile |  9 +++++++--
 qrap.c   | 42 ++++++++++++++++++++++++++----------------
 2 files changed, 33 insertions(+), 18 deletions(-)

diff --git a/Makefile b/Makefile
index d29f46d2..7875d23b 100644
--- a/Makefile
+++ b/Makefile
@@ -183,7 +183,7 @@ docs: README.md
 CLANG_TIDY = clang-tidy
 CLANG_TIDY_FLAGS = -DCLANG_TIDY_58992
 
-clang-tidy: passt.clang-tidy passt-repair.clang-tidy
+clang-tidy: passt.clang-tidy passt-repair.clang-tidy qrap.clang-tidy
 
 .PHONY: %.clang-tidy
 %.clang-tidy:
@@ -191,6 +191,7 @@ clang-tidy: passt.clang-tidy passt-repair.clang-tidy
 
 passt.clang-tidy: $(PASST_SRCS) $(PASST_HEADERS) seccomp.h
 passt-repair.clang-tidy: $(PASST_REPAIR_SRCS) $(PASST_REPAIR_HEADERS) seccomp_repair.h
+qrap.clang-tidy: $(QRAP_SRCS) $(QRAP_HEADERS)
 
 CPPCHECK = cppcheck
 CPPCHECK_FLAGS = --std=c11 --error-exitcode=1 --enable=all --force	\
@@ -205,7 +206,7 @@ CPPCHECK_FLAGS = --std=c11 --error-exitcode=1 --enable=all --force	\
 	--suppress=unusedStructMember					\
 	 -D CPPCHECK_6936
 
-cppcheck: passt.cppcheck passt-repair.cppcheck
+cppcheck: passt.cppcheck passt-repair.cppcheck qrap.cppcheck
 
 .PHONY: %.cppcheck
 %.cppcheck:
@@ -213,3 +214,7 @@ cppcheck: passt.cppcheck passt-repair.cppcheck
 
 passt.cppcheck: $(PASST_SRCS) $(PASST_HEADERS) seccomp.h
 passt-repair.cppcheck: $(PASST_REPAIR_SRCS) $(PASST_REPAIR_HEADERS) seccomp_repair.h
+
+qrap.cppcheck: BASE_CPPFLAGS += -DARCH=\"$(TARGET_ARCH)\"
+qrap.cppcheck: CPPCHECK_FLAGS += --suppress=unusedFunction
+qrap.cppcheck: $(QRAP_SRCS) $(QRAP_HEADERS)
diff --git a/qrap.c b/qrap.c
index d5967062..4a01ed83 100644
--- a/qrap.c
+++ b/qrap.c
@@ -46,6 +46,15 @@ static char *qemu_names[] = {
 	NULL,
 };
 
+#define BUILDARG(s_, ...)						\
+	do {								\
+		static_assert(sizeof(s_) == ARG_MAX, "Bad buffer size"); \
+		if (snprintf((s_), ARG_MAX, __VA_ARGS__) >= ARG_MAX) {	\
+			FPRINTF(stderr, "Arguments too long");		\
+			exit(EXIT_FAILURE);				\
+		}							\
+	} while (0)
+
 /**
  * struct drop_arg - Drop matching arguments on command line
  * @name:	Option name
@@ -120,11 +129,11 @@ static const struct pci_dev {
  * usage() - Print usage and exit
  * @name:	Executable name
  */
-void usage(const char *name)
+static void usage(const char *name)
 {
-	fprintf(stderr, "Usage: %s [FDNUM QEMU_CMD] [QEMU_ARG]...\n", name);
-	fprintf(stderr, "\n");
-	fprintf(stderr, "If first and second arguments aren't a socket number\n"
+	FPRINTF(stderr, "Usage: %s [FDNUM QEMU_CMD] [QEMU_ARG]...\n", name);
+	FPRINTF(stderr, "\n");
+	FPRINTF(stderr, "If first and second arguments aren't a socket number\n"
 			"and a path, %s will try to locate a qemu binary\n"
 			"and directly patch the command line\n", name);
 
@@ -202,13 +211,14 @@ int main(int argc, char **argv)
 		errno = 0;
 		fd = strtol(argv[1], NULL, 0);
 		if (fd >= 3 && fd < INT_MAX && !errno && path) {
-			char env_path[ARG_MAX + 1], *p, command[ARG_MAX];
+			char env_path[ARG_MAX + 1], command[ARG_MAX];
+			const char *p;
 
 			strncpy(env_path, path, ARG_MAX);
 			/* cppcheck-suppress strtokCalled */
 			p = strtok(env_path, ":");
 			while (p) {
-				snprintf(command, ARG_MAX, "%s/%s", p, argv[2]);
+				BUILDARG(command, "%s/%s", p, argv[2]);
 				if (!access(command, X_OK))
 					goto valid_args;
 
@@ -281,7 +291,7 @@ int main(int argc, char **argv)
 			break;
 	}
 	if (i == dev->last) {
-		fprintf(stderr, "Couldn't find free address for device\n");
+		FPRINTF(stderr, "Couldn't find free address for device\n");
 		usage(argv[0]);
 	}
 
@@ -289,21 +299,21 @@ int main(int argc, char **argv)
 		qemu_argv[qemu_argc++] = "-device";
 		if (!has_json) {
 			if (dev->base == 16) {
-				snprintf(dev_str, ARG_MAX,
-				         "%s,%s%x%s,netdev=hostnet0,x-txburst=4096",
+				BUILDARG(dev_str,
+					 "%s,%s%x%s,netdev=hostnet0,x-txburst=4096",
 				         dev->name, dev->template, i, dev->template_post);
 			} else if (dev->base == 10) {
-				snprintf(dev_str, ARG_MAX,
+				BUILDARG(dev_str,
 				         "%s,%s%d%s,netdev=hostnet0,x-txburst=4096",
 				         dev->name, dev->template, i, dev->template_post);
 			}
 		} else {
 			if (dev->base == 16) {
-				snprintf(dev_str, ARG_MAX,
+				BUILDARG(dev_str,
 				         "{\"driver\":\"%s\",%s%x\"%s,\"netdev\":\"hostnet0\",\"x-txburst\":4096}",
 				         dev->name, dev->template_json, i, dev->template_json_post);
 			} else if (dev->base == 10) {
-				snprintf(dev_str, ARG_MAX,
+				BUILDARG(dev_str,
 				         "{\"driver\":\"%s\",%s%d\"%s,\"netdev\":\"hostnet0\",\"x-txburst\":4096}",
 				         dev->name, dev->template_json, i, dev->template_json_post);
 			}
@@ -335,7 +345,7 @@ retry:
 		if (setsockopt(s, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv)))
 			perror("setsockopt SO_SNDTIMEO");
 
-		snprintf(addr.sun_path, UNIX_PATH_MAX, UNIX_SOCK_PATH, i);
+		(void)snprintf(addr.sun_path, UNIX_PATH_MAX, UNIX_SOCK_PATH, i);
 
 		errno = 0;
 
@@ -381,7 +391,7 @@ retry:
 			goto retry;
 		}
 
-		fprintf(stderr, "Probe of %s failed\n", addr.sun_path);
+		FPRINTF(stderr, "Probe of %s failed\n", addr.sun_path);
 
 		close(s);
 	}
@@ -397,7 +407,7 @@ retry:
 	if (setsockopt(s, SOL_SOCKET, SO_SNDTIMEO, &tv, sizeof(tv)))
 		perror("setsockopt, SO_SNDTIMEO reset");
 
-	fprintf(stderr, "Connected to %s\n", addr.sun_path);
+	FPRINTF(stderr, "Connected to %s\n", addr.sun_path);
 
 	if (dup2(s, (int)fd) < 0) {
 		perror("dup");
@@ -418,7 +428,7 @@ retry:
 			}
 		}
 		if (errno == ENOENT)
-			fprintf(stderr, "Couldn't find qemu command\n");
+			FPRINTF(stderr, "Couldn't find qemu command\n");
 	} else {
 		execvp(argv[2], argv + 2);
 	}
-- 
2.53.0