tests: wait for gpiochips before running tests

We're currently using an ugly hack to check if gpiochip files are
actually mockup chips. Remove it and use libudev instead to poll for
uevents until all mockup GPIO devices appear in /dev.

Signed-off-by: Bartosz Golaszewski <bartekgola@gmail.com>

diff --git a/configure.ac b/configure.ac
index 4572987fdc39f018a467ed737ed0fb40ed62e40f..9b79797447073f3bd163efba2b4f1dd368028393 100644 (file)
--- a/configure.ac
+++ b/configure.ac
@@ -106,7 +106,10 @@ if test "x$with_tools" = xtrue
 then
        AC_CHECK_LIB([kmod], [kmod_module_probe_insert_module], [],
                [AC_MSG_ERROR([libkmod not found (needed to build tests])])
+       AC_CHECK_LIB([udev], [udev_monitor_new_from_netlink], [],
+               [AC_MSG_ERROR([libudev not found (needed to build tests])])
        AC_CHECK_HEADERS([libkmod.h], [], [HEADER_NOT_FOUND_TESTS([libkmod.h])])
+       AC_CHECK_HEADERS([libudev.h], [], [HEADER_NOT_FOUND_TESTS([libudev.h])])
        AC_CHECK_FUNC([qsort], [], [FUNC_NOT_FOUND_TESTS([qsort])])
 fi
 

diff --git a/tests/unit/Makefile.am b/tests/unit/Makefile.am
index 3e216cc488dd02cbb06a7f730dcba4a8f43a8877..6d72d16c8be73ac989ec6cc870118bcdde7a2e1a 100644 (file)
--- a/tests/unit/Makefile.am
+++ b/tests/unit/Makefile.am
@@ -8,7 +8,7 @@
 
 AM_CFLAGS = -I$(top_srcdir)/include/ -include $(top_srcdir)/config.h
 AM_CFLAGS += -Wall -Wextra -g
-LDADD = -lgpiod -L$(top_srcdir)/src/lib -lkmod
+LDADD = -lgpiod -L$(top_srcdir)/src/lib -lkmod -ludev
 DEPENDENCIES = libgpiod.la
 
 check_PROGRAMS = gpiod-unit

diff --git a/tests/unit/gpiod-unit.c b/tests/unit/gpiod-unit.c
index 4e0e6ccce96bdb9b5c5a5da76ee1508bb135ad58..5512ae4dde0a75d4469dac4b43eea70135a274fd 100644 (file)
--- a/tests/unit/gpiod-unit.c
+++ b/tests/unit/gpiod-unit.c
@@ -14,16 +14,15 @@
 #include <string.h>
 #include <stdarg.h>
 #include <errno.h>
-#include <time.h>
-#include <dirent.h>
 #include <unistd.h>
-#include <sys/stat.h>
-#include <sys/types.h>
-#include <sys/time.h>
+#include <poll.h>
 #include <libkmod.h>
+#include <libudev.h>
 
 #define NORETURN __attribute__((noreturn))
 
+static const char mockup_devpath[] = "/devices/platform/gpio-mockup/gpiochip";
+
 struct mockup_chip {
        char *path;
        char *name;
@@ -34,7 +33,6 @@ struct test_context {
        struct mockup_chip **chips;
        size_t num_chips;
        bool test_failed;
-       struct timeval mod_loaded_ts;
 };
 
 static struct {
@@ -120,21 +118,6 @@ static char * xstrdup(const char *str)
        return ret;
 }
 
-static GU_PRINTF(1, 2) char * xasprintf(const char *fmt, ...)
-{
-       int status;
-       va_list va;
-       char *ret;
-
-       va_start(va, fmt);
-       status = vasprintf(&ret, fmt, va);
-       if (status < 0)
-               die_perr("asprintf");
-       va_end(va);
-
-       return ret;
-}
-
 static GU_PRINTF(2, 3) char * xcasprintf(size_t *count, const char *fmt, ...)
 {
        int status;
@@ -296,7 +279,6 @@ static void test_load_module(struct gu_chip_descr *descr)
 
        modarg[modarg_len - 1] = '\0'; /* Remove the last comma. */
 
-       gettimeofday(&globals.test_ctx.mod_loaded_ts, NULL);
        status = kmod_module_probe_insert_module(globals.module, 0,
                                                 modarg, NULL, NULL, NULL);
        if (status)
@@ -308,31 +290,6 @@ static void test_load_module(struct gu_chip_descr *descr)
        free(line_sizes);
 }
 
-/*
- * To see if given chip is a mockup chip, check if it was created after
- * inserting the gpio-mockup module. It's not too clever, but works well
- * enough...
- */
-static bool is_mockup_chip(const char *name)
-{
-       struct timeval gdev_created_ts;
-       struct stat gdev_stat;
-       char *path;
-       int status;
-
-       path = xasprintf("/dev/%s", name);
-
-       status = stat(path, &gdev_stat);
-       free(path);
-       if (status < 0)
-               die_perr("stat");
-
-       gdev_created_ts.tv_sec = gdev_stat.st_ctim.tv_sec;
-       gdev_created_ts.tv_usec = gdev_stat.st_ctim.tv_nsec / 1000;
-
-       return timercmp(&globals.test_ctx.mod_loaded_ts, &gdev_created_ts, >=);
-}
-
 static int chipcmp(const void *c1, const void *c2)
 {
        const struct mockup_chip *chip1 = *(const struct mockup_chip **)c1;
@@ -341,48 +298,90 @@ static int chipcmp(const void *c1, const void *c2)
        return strcmp(chip1->name, chip2->name);
 }
 
+static bool devpath_is_mockup(const char *devpath)
+{
+       return !strncmp(devpath, mockup_devpath, sizeof(mockup_devpath) - 1);
+}
+
 static void test_prepare(struct gu_chip_descr *descr)
 {
+       const char *devpath, *devnode, *sysname;
+       struct udev_monitor *monitor;
+       unsigned int detected = 0;
        struct test_context *ctx;
        struct mockup_chip *chip;
-       unsigned int current = 0;
-       struct dirent *dentry;
+       struct udev_device *dev;
+       struct udev *udev_ctx;
+       struct pollfd pfd;
        int status;
-       DIR *dir;
 
        ctx = &globals.test_ctx;
        memset(ctx, 0, sizeof(*ctx));
+       ctx->num_chips = descr->num_chips;
+       ctx->chips = xzalloc(sizeof(*ctx->chips) * ctx->num_chips);
+
+       /*
+        * We'll setup the udev monitor, insert the module and wait for the
+        * mockup gpiochips to appear.
+        */
+
+       udev_ctx = udev_new();
+       if (!udev_ctx)
+               die_perr("error creating udev context");
+
+       monitor = udev_monitor_new_from_netlink(udev_ctx, "udev");
+       if (!monitor)
+               die_perr("error creating udev monitor");
+
+       status = udev_monitor_filter_add_match_subsystem_devtype(monitor,
+                                                                "gpio", NULL);
+       if (status < 0)
+               die_perr("error adding udev filters");
+
+       status = udev_monitor_enable_receiving(monitor);
+       if (status < 0)
+               die_perr("error enabling udev event receiving");
 
        test_load_module(descr);
 
-       ctx->num_chips = descr->num_chips;
-       ctx->chips = xzalloc(sizeof(*ctx->chips) * ctx->num_chips);
+       pfd.fd = udev_monitor_get_fd(monitor);
+       pfd.events = POLLIN | POLLPRI;
+
+       while (ctx->num_chips > detected) {
+               status = poll(&pfd, 1, 5000);
+               if (status < 0)
+                       die_perr("error polling for uevents");
+               else if (status == 0)
+                       die("timeout waiting for gpiochips");
+
+               dev = udev_monitor_receive_device(monitor);
+               if (!dev)
+                       die_perr("error reading device info");
 
-       dir = opendir("/dev");
-       if (!dir)
-               die_perr("error opening /dev");
+               devpath = udev_device_get_devpath(dev);
+               devnode = udev_device_get_devnode(dev);
+               sysname = udev_device_get_sysname(dev);
+               if (!devpath || !devnode || !sysname)
+                       goto cont;
 
-       for (dentry = readdir(dir); dentry; dentry = readdir(dir)) {
-               if (strncmp(dentry->d_name, "gpiochip", 8) == 0) {
-                       if (!is_mockup_chip(dentry->d_name))
-                               continue;
+               if (!devpath_is_mockup(devpath))
+                       goto cont;
 
-                       chip = xzalloc(sizeof(*chip));
-                       ctx->chips[current++] = chip;
+               chip = xzalloc(sizeof(*chip));
+               chip->name = xstrdup(sysname);
+               chip->path = xstrdup(devnode);
+               status = sscanf(sysname, "gpiochip%u", &chip->number);
+               if (status != 1)
+                       die("unable to determine chip number");
 
-                       chip->name = xstrdup(dentry->d_name);
-                       chip->path = xasprintf("/dev/%s", dentry->d_name);
+               ctx->chips[detected++] = chip;
 
-                       status = sscanf(dentry->d_name,
-                                       "gpiochip%u", &chip->number);
-                       if (status != 1)
-                               die("unable to determine the chip number");
-               }
+cont:
+               udev_device_unref(dev);
        }
-       closedir(dir);
 
-       if (descr->num_chips != current)
-               die("number of requested and detected mockup gpiochips is not the same");
+       udev_monitor_unref(monitor);
+       udev_unref(udev_ctx);
 
        qsort(ctx->chips, ctx->num_chips, sizeof(*ctx->chips), chipcmp);
 }