Revert component-split

this reverts the commits from 92ab9ef52ebcb097add97d9f78e67ad1c1d6a6ec up to
d42870d6ca7fb587b38f8cf6d6821ae33a53a696.

After heavy consideration, the component split has more disadvantages
than advantages, especially given there will be utility-functions
sharing quite a lot of code that would then need to be duplicated, as it
does not fit into the util.c due to its speciality.

One big advantage of the component-wise build is readability, and
without doubt, this was achieved here. This point will be addressed
with a different approach that will be visible in the upcoming commits.

One big disadvantage of the component build is the fact that it
introduces state to the build process which is not necessary. Before its
introduction, the only influencing factors where the system-defines
__linux__ and __OpenBSD__. With the components, we are also relying on
the output of uname(1).
Additionally, if the os.mk is not present, make gives the output

     $ make
     Makefile:5: os.mk: No such file or directory
     make: *** No rule to make target 'os.mk'.  Stop.

This could easily be fixed by providing some sort of meta-rule for this
file, however, it indicates the problem we have here, and this entire
statefulness will heavily complicate packaging of this tool and makes
the build process much more complex than it actually has to be.

17 files changed, 235 insertions, 233 deletions

diff --git a/components/Linux/ram.c b/components/Linux/ram.c
deleted file mode 100644
index 7df5f85..0000000
--- a/components/Linux/ram.c
+++ /dev/null
@@ -1,52 +0,0 @@
-/* See LICENSE file for copyright and license details. */
-#include <stdio.h>
-
-#include "../../util.h"
-
-const char *
-ram_free(void)
-{
-	long free;
-
-	return (pscanf("/proc/meminfo", "MemFree: %ld kB\n", &free) == 1) ?
-	       bprintf("%f", (float)free / 1024 / 1024) : NULL;
-}
-
-const char *
-ram_perc(void)
-{
-	long total, free, buffers, cached;
-
-	return (pscanf("/proc/meminfo",
-	               "MemTotal: %ld kB\n"
-	               "MemFree: %ld kB\n"
-	               "MemAvailable: %ld kB\nBuffers: %ld kB\n"
-	               "Cached: %ld kB\n",
-	               &total, &free, &buffers, &buffers, &cached) == 5) ?
-	       bprintf("%d", 100 * ((total - free) - (buffers + cached)) / total) :
-	       NULL;
-}
-
-const char *
-ram_total(void)
-{
-	long total;
-
-	return (pscanf("/proc/meminfo", "MemTotal: %ld kB\n", &total) == 1) ?
-	       bprintf("%f", (float)total / 1024 / 1024) : NULL;
-}
-
-const char *
-ram_used(void)
-{
-	long total, free, buffers, cached;
-
-	return (pscanf("/proc/meminfo",
-	               "MemTotal: %ld kB\n"
-	               "MemFree: %ld kB\n"
-	               "MemAvailable: %ld kB\nBuffers: %ld kB\n"
-	               "Cached: %ld kB\n",
-	               &total, &free, &buffers, &buffers, &cached) == 5) ?
-	       bprintf("%f", (float)(total - free - buffers - cached) / 1024 / 1024) :
-	       NULL;
-}
diff --git a/components/Linux/temperature.c b/components/Linux/temperature.c
deleted file mode 100644
index fa50826..0000000
--- a/components/Linux/temperature.c
+++ /dev/null
@@ -1,15 +0,0 @@
-/* See LICENSE file for copyright and license details. */
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-
-#include "../../util.h"
-
-const char *
-temp(const char *file)
-{
-	int temp;
-
-	return (pscanf(file, "%d", &temp) == 1) ?
-	       bprintf("%d", temp / 1000) : NULL;
-}
diff --git a/components/Linux/uptime.c b/components/Linux/uptime.c
deleted file mode 100644
index e7afc8e..0000000
--- a/components/Linux/uptime.c
+++ /dev/null
@@ -1,24 +0,0 @@
-/* See LICENSE file for copyright and license details. */
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-#include <sys/sysinfo.h>
-
-#include "../../util.h"
-
-const char *
-uptime(void)
-{
-	int h;
-	int m;
-	int uptime = 0;
-	struct sysinfo info;
-
-	sysinfo(&info);
-	uptime = info.uptime;
-
-	h = uptime / 3600;
-	m = (uptime - h * 3600) / 60;
-
-	return bprintf("%dh %dm", h, m);
-}
diff --git a/components/OpenBSD/battery.c b/components/OpenBSD/battery.c
deleted file mode 100644
index daefd77..0000000
--- a/components/OpenBSD/battery.c
+++ /dev/null
@@ -1,32 +0,0 @@
-/* See LICENSE file for copyright and license details. */
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-#include <sys/ioctl.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <machine/apmvar.h>
-
-#include "../../util.h"
-
-const char *
-battery_perc(const char *null)
-{
-	struct apm_power_info apm_info;
-	int fd;
-
-	fd = open("/dev/apm", O_RDONLY);
-	if (fd < 0) {
-		fprintf(stderr, "open '/dev/apm': %s\n", strerror(errno));
-		return NULL;
-	}
-
-	if (ioctl(fd, APM_IOC_GETPOWER, &apm_info) < 0) {
-		fprintf(stderr, "ioctl 'APM_IOC_GETPOWER': %s\n", strerror(errno));
-		close(fd);
-		return NULL;
-	}
-	close(fd);
-
-	return bprintf("%d", apm_info.battery_life);
-}
diff --git a/components/OpenBSD/cpu.c b/components/OpenBSD/cpu.c
deleted file mode 100644
index 11f1812..0000000
--- a/components/OpenBSD/cpu.c
+++ /dev/null
@@ -1,26 +0,0 @@
-/* See LICENSE file for copyright and license details. */
-#include <errno.h>
-#include <stdio.h>
-#include <string.h>
-#include <sys/sysctl.h>
-
-#include "../../util.h"
-
-const char *
-cpu_freq(void)
-{
-	int freq, mib[2];
-	size_t size;
-
-	mib[0] = CTL_HW;
-	mib[1] = HW_CPUSPEED;
-
-	size = sizeof(freq);
-
-	if (sysctl(mib, 2, &freq, &size, NULL, 0) == -1) {
-		fprintf(stderr, "sysctl 'HW_CPUSPEED': %s\n", strerror(errno));
-		return NULL;
-	}
-
-	return bprintf("%d", freq);
-}
diff --git a/components/OpenBSD/entropy.c b/components/OpenBSD/entropy.c
deleted file mode 100644
index e69de29..0000000
--- a/components/OpenBSD/entropy.c
+++ /dev/null
diff --git a/components/OpenBSD/ram.c b/components/OpenBSD/ram.c
deleted file mode 100644
index f7c81d1..0000000
--- a/components/OpenBSD/ram.c
+++ /dev/null
@@ -1,77 +0,0 @@
-/* See LICENSE file for copyright and license details. */
-#include <stdio.h>
-#include <sys/types.h>
-#include <sys/sysctl.h>
-#include <stdlib.h>
-#include <unistd.h>
-
-#include "../../util.h"
-
-inline int
-load_uvmexp(struct uvmexp *uvmexp)
-{
-	int uvmexp_mib[] = {CTL_VM, VM_UVMEXP};
-	size_t size;
-
-	size = sizeof(*uvmexp);
-
-	return sysctl(uvmexp_mib, 2, uvmexp, &size, NULL, 0) >= 0 ? 1 : 0;
-}
-
-const char *
-ram_free(void)
-{
-	struct uvmexp uvmexp;
-	float free;
-	int free_pages;
-
-	if (load_uvmexp(&uvmexp)) {
-		free_pages = uvmexp.npages - uvmexp.active;
-		free = (double) (free_pages * uvmexp.pagesize) / 1024 / 1024 / 1024;
-		return bprintf("%f", free);
-	}
-
-	return NULL;
-}
-
-const char *
-ram_perc(void)
-{
-	struct uvmexp uvmexp;
-	int percent;
-
-	if (load_uvmexp(&uvmexp)) {
-		percent = uvmexp.active * 100 / uvmexp.npages;
-		return bprintf("%d", percent);
-	}
-
-	return NULL;
-}
-
-const char *
-ram_total(void)
-{
-	struct uvmexp uvmexp;
-	float total;
-
-	if (load_uvmexp(&uvmexp)) {
-		total = (double) (uvmexp.npages * uvmexp.pagesize) / 1024 / 1024 / 1024;
-		return bprintf("%f", total);
-	}
-
-	return NULL;
-}
-
-const char *
-ram_used(void)
-{
-	struct uvmexp uvmexp;
-	float used;
-
-	if (load_uvmexp(&uvmexp)) {
-		used = (double) (uvmexp.active * uvmexp.pagesize) / 1024 / 1024 / 1024;
-		return bprintf("%f", used);
-	}
-
-	return NULL;
-}
diff --git a/components/OpenBSD/swap.c b/components/OpenBSD/swap.c
deleted file mode 100644
index e69de29..0000000
--- a/components/OpenBSD/swap.c
+++ /dev/null
diff --git a/components/OpenBSD/wifi.c b/components/OpenBSD/wifi.c
deleted file mode 100644
index e69de29..0000000
--- a/components/OpenBSD/wifi.c
+++ /dev/null
diff --git a/components/Linux/battery.c b/components/battery.c
index 654ddab..955d8ab 100644
--- a/components/Linux/battery.c
+++ b/components/battery.c
@@ -2,11 +2,19 @@
 #include <errno.h>
 #include <stdio.h>
 #include <string.h>
+#if defined(__linux__)
 #include <limits.h>
 #include <string.h>
+#elif defined(__OpenBSD__)
+#include <sys/ioctl.h>
+#include <fcntl.h>
+#include <unistd.h>
+#include <machine/apmvar.h>
+#endif
 
-#include "../../util.h"
+#include "../util.h"
 
+#if defined(__linux__)
 const char *
 battery_perc(const char *bat)
 {
@@ -17,7 +25,31 @@ battery_perc(const char *bat)
 	return (pscanf(path, "%i", &perc) == 1) ?
 	       bprintf("%d", perc) : NULL;
 }
+#elif defined(__OpenBSD__)
+const char *
+battery_perc(const char *null)
+{
+	struct apm_power_info apm_info;
+	int fd;
+
+	fd = open("/dev/apm", O_RDONLY);
+	if (fd < 0) {
+		fprintf(stderr, "open '/dev/apm': %s\n", strerror(errno));
+		return NULL;
+	}
+
+	if (ioctl(fd, APM_IOC_GETPOWER, &apm_info) < 0) {
+		fprintf(stderr, "ioctl 'APM_IOC_GETPOWER': %s\n", strerror(errno));
+		close(fd);
+		return NULL;
+	}
+	close(fd);
+
+	return bprintf("%d", apm_info.battery_life);
+}
+#endif
 
+#if defined(__linux__)
 const char *
 battery_power(const char *bat)
 {
@@ -56,3 +88,4 @@ battery_state(const char *bat)
 	}
 	return (i == LEN(map)) ? "?" : map[i].symbol;
 }
+#endif
diff --git a/components/Linux/cpu.c b/components/cpu.c
index bfc204c..11e2e98 100644
--- a/components/Linux/cpu.c
+++ b/components/cpu.c
@@ -2,9 +2,13 @@
 #include <errno.h>
 #include <stdio.h>
 #include <string.h>
+#if defined(__OpenBSD__)
+#include <sys/sysctl.h>
+#endif
 
-#include "../../util.h"
+#include "../util.h"
 
+#if defined(__linux__)
 const char *
 cpu_freq(void)
 {
@@ -62,3 +66,23 @@ cpu_iowait(void)
 
 	return bprintf("%d", perc);
 }
+#elif defined(__OpenBSD__)
+const char *
+cpu_freq(void)
+{
+	int freq, mib[2];
+	size_t size;
+
+	mib[0] = CTL_HW;
+	mib[1] = HW_CPUSPEED;
+
+	size = sizeof(freq);
+
+	if (sysctl(mib, 2, &freq, &size, NULL, 0) == -1) {
+		fprintf(stderr, "sysctl 'HW_CPUSPEED': %s\n", strerror(errno));
+		return NULL;
+	}
+
+	return bprintf("%d", freq);
+}
+#endif
diff --git a/components/Linux/entropy.c b/components/entropy.c
index 17be270..65c65a1 100644
--- a/components/Linux/entropy.c
+++ b/components/entropy.c
@@ -1,7 +1,8 @@
 /* See LICENSE file for copyright and license details. */
+#if defined(__linux__)
 #include <stdio.h>
 
-#include "../../util.h"
+#include "../util.h"
 
 const char *
 entropy(void)
@@ -11,3 +12,4 @@ entropy(void)
 	return (pscanf("/proc/sys/kernel/random/entropy_avail", "%d", &num) == 1) ?
 	               bprintf("%d", num) : NULL;
 }
+#endif
diff --git a/components/ram.c b/components/ram.c
new file mode 100644
index 0000000..55ec5b9
--- /dev/null
+++ b/components/ram.c
@@ -0,0 +1,129 @@
+/* See LICENSE file for copyright and license details. */
+#include <stdio.h>
+#if defined (__OpenBSD__)
+#include <sys/types.h>
+#include <sys/sysctl.h>
+#include <stdlib.h>
+#include <unistd.h>
+#endif
+
+#include "../util.h"
+
+#if defined(__linux__)
+const char *
+ram_free(void)
+{
+	long free;
+
+	return (pscanf("/proc/meminfo", "MemFree: %ld kB\n", &free) == 1) ?
+	       bprintf("%f", (float)free / 1024 / 1024) : NULL;
+}
+
+const char *
+ram_perc(void)
+{
+	long total, free, buffers, cached;
+
+	return (pscanf("/proc/meminfo",
+	               "MemTotal: %ld kB\n"
+	               "MemFree: %ld kB\n"
+	               "MemAvailable: %ld kB\nBuffers: %ld kB\n"
+	               "Cached: %ld kB\n",
+	               &total, &free, &buffers, &buffers, &cached) == 5) ?
+	       bprintf("%d", 100 * ((total - free) - (buffers + cached)) / total) :
+	       NULL;
+}
+
+const char *
+ram_total(void)
+{
+	long total;
+
+	return (pscanf("/proc/meminfo", "MemTotal: %ld kB\n", &total) == 1) ?
+	       bprintf("%f", (float)total / 1024 / 1024) : NULL;
+}
+
+const char *
+ram_used(void)
+{
+	long total, free, buffers, cached;
+
+	return (pscanf("/proc/meminfo",
+	               "MemTotal: %ld kB\n"
+	               "MemFree: %ld kB\n"
+	               "MemAvailable: %ld kB\nBuffers: %ld kB\n"
+	               "Cached: %ld kB\n",
+	               &total, &free, &buffers, &buffers, &cached) == 5) ?
+	       bprintf("%f", (float)(total - free - buffers - cached) / 1024 / 1024) :
+	       NULL;
+}
+#elif defined(__OpenBSD__)
+inline int
+load_uvmexp(struct uvmexp *uvmexp)
+{
+	int uvmexp_mib[] = {CTL_VM, VM_UVMEXP};
+	size_t size;
+
+	size = sizeof(*uvmexp);
+
+	return sysctl(uvmexp_mib, 2, uvmexp, &size, NULL, 0) >= 0 ? 1 : 0;
+}
+
+const char *
+ram_free(void)
+{
+	struct uvmexp uvmexp;
+	float free;
+	int free_pages;
+
+	if (load_uvmexp(&uvmexp)) {
+		free_pages = uvmexp.npages - uvmexp.active;
+		free = (double) (free_pages * uvmexp.pagesize) / 1024 / 1024 / 1024;
+		return bprintf("%f", free);
+	}
+
+	return NULL;
+}
+
+const char *
+ram_perc(void)
+{
+	struct uvmexp uvmexp;
+	int percent;
+
+	if (load_uvmexp(&uvmexp)) {
+		percent = uvmexp.active * 100 / uvmexp.npages;
+		return bprintf("%d", percent);
+	}
+
+	return NULL;
+}
+
+const char *
+ram_total(void)
+{
+	struct uvmexp uvmexp;
+	float total;
+
+	if (load_uvmexp(&uvmexp)) {
+		total = (double) (uvmexp.npages * uvmexp.pagesize) / 1024 / 1024 / 1024;
+		return bprintf("%f", total);
+	}
+
+	return NULL;
+}
+
+const char *
+ram_used(void)
+{
+	struct uvmexp uvmexp;
+	float used;
+
+	if (load_uvmexp(&uvmexp)) {
+		used = (double) (uvmexp.active * uvmexp.pagesize) / 1024 / 1024 / 1024;
+		return bprintf("%f", used);
+	}
+
+	return NULL;
+}
+#endif
diff --git a/components/Linux/swap.c b/components/swap.c
index bce9d5a..f3bbeb2 100644
--- a/components/Linux/swap.c
+++ b/components/swap.c
@@ -1,9 +1,10 @@
 /* See LICENSE file for copyright and license details. */
+#if defined(__linux__)
 #include <errno.h>
 #include <stdio.h>
 #include <string.h>
 
-#include "../../util.h"
+#include "../util.h"
 
 const char *
 swap_free(void)
@@ -134,3 +135,4 @@ swap_used(void)
 
 	return bprintf("%f", (float)(total - free - cached) / 1024 / 1024);
 }
+#endif
diff --git a/components/OpenBSD/temperature.c b/components/temperature.c
index 8098868..e2c6a77 100644
--- a/components/OpenBSD/temperature.c
+++ b/components/temperature.c
@@ -2,12 +2,24 @@
 #include <errno.h>
 #include <stdio.h>
 #include <string.h>
+#if defined(__OpenBSD__)
 #include <sys/sysctl.h>
 #include <sys/time.h>
 #include <sys/sensors.h>
+#endif
 
-#include "../../util.h"
+#include "../util.h"
 
+#if defined(__linux__)
+const char *
+temp(const char *file)
+{
+	int temp;
+
+	return (pscanf(file, "%d", &temp) == 1) ?
+	       bprintf("%d", temp / 1000) : NULL;
+}
+#elif defined(__OpenBSD__)
 const char *
 temp(const char *null)
 {
@@ -30,3 +42,4 @@ temp(const char *null)
 
 	return bprintf("%d", (temp.value - 273150000) / 1000000); /* kelvin to celsius */
 }
+#endif
diff --git a/components/OpenBSD/uptime.c b/components/uptime.c
index 637e2e0..debe4cb 100644
--- a/components/OpenBSD/uptime.c
+++ b/components/uptime.c
@@ -2,11 +2,33 @@
 #include <errno.h>
 #include <stdio.h>
 #include <string.h>
+#if defined(__linux__)
+#include <sys/sysinfo.h>
+#elif defined(__OpenBSD__)
 #include <sys/sysctl.h>
 #include <sys/time.h>
+#endif
 
-#include "../../util.h"
+#include "../util.h"
 
+#if defined(__linux__)
+const char *
+uptime(void)
+{
+	int h;
+	int m;
+	int uptime = 0;
+	struct sysinfo info;
+
+	sysinfo(&info);
+	uptime = info.uptime;
+
+	h = uptime / 3600;
+	m = (uptime - h * 3600) / 60;
+
+	return bprintf("%dh %dm", h, m);
+}
+#elif defined(__OpenBSD__)
 const char *
 uptime(void)
 {
@@ -38,3 +60,4 @@ uptime(void)
 
 	return bprintf("%dh %dm", h, m);
 }
+#endif
diff --git a/components/Linux/wifi.c b/components/wifi.c
index e86fcbc..388a30d 100644
--- a/components/Linux/wifi.c
+++ b/components/wifi.c
@@ -1,4 +1,5 @@
 /* See LICENSE file for copyright and license details. */
+#if defined(__linux__)
 #include <errno.h>
 #include <ifaddrs.h>
 #include <linux/wireless.h>
@@ -9,7 +10,7 @@
 #include <sys/ioctl.h>
 #include <unistd.h>
 
-#include "../../util.h"
+#include "../util.h"
 
 const char *
 wifi_perc(const char *iface)
@@ -88,3 +89,4 @@ wifi_essid(const char *iface)
 	else
 		return id;
 }
+#endif