lib: Add mlibc

Signed-off-by: Ian Moffett <ian@osmora.org>

1 files changed, 71 insertions, 0 deletions

diff --git a/lib/mlibc/options/linux/generic/cpuset.cpp b/lib/mlibc/options/linux/generic/cpuset.cpp
new file mode 100644
index 0000000..d0292b7
--- /dev/null
+++ b/lib/mlibc/options/linux/generic/cpuset.cpp
@@ -0,0 +1,71 @@
+#include <limits.h>
+#include <sched.h>
+#include <stdlib.h>
+#include <string.h>
+
+cpu_set_t *__mlibc_cpu_alloc(int num_cpus) {
+	return reinterpret_cast<cpu_set_t *>(calloc(1, CPU_ALLOC_SIZE(num_cpus)));
+}
+
+#define CPU_MASK_BITS (CHAR_BIT * sizeof(__cpu_mask))
+
+size_t __mlibc_cpu_alloc_size(int num_cpus) {
+	/* calculate the (unaligned) remainder that doesn't neatly fit in one __cpu_mask; 0 or 1 */
+	size_t remainder = ((num_cpus % CPU_MASK_BITS) + CPU_MASK_BITS - 1) / CPU_MASK_BITS;
+	return sizeof(__cpu_mask) * (num_cpus / CPU_MASK_BITS + remainder);
+}
+
+void __mlibc_cpu_zero(const size_t setsize, cpu_set_t *set) {
+	memset(set, 0, CPU_ALLOC_SIZE(setsize));
+}
+
+void __mlibc_cpu_set(const int cpu, const size_t setsize, cpu_set_t *set) {
+	if(cpu >= static_cast<int>(setsize * CHAR_BIT)) {
+		return;
+	}
+
+	unsigned char *ptr = reinterpret_cast<unsigned char *>(set);
+	size_t off = cpu / CHAR_BIT;
+	size_t mask = 1 << (cpu % CHAR_BIT);
+
+	ptr[off] |= mask;
+}
+
+void __mlibc_cpu_clear(const int cpu, const size_t setsize, cpu_set_t *set) {
+	if(cpu >= static_cast<int>(setsize * CHAR_BIT)) {
+		return;
+	}
+
+	unsigned char *ptr = reinterpret_cast<unsigned char *>(set);
+	size_t off = cpu / CHAR_BIT;
+	size_t mask = 1 << (cpu % CHAR_BIT);
+
+	ptr[off] &= ~mask;
+}
+
+
+int __mlibc_cpu_isset(const int cpu, const size_t setsize, const cpu_set_t *set) {
+	if(cpu >= static_cast<int>(setsize * CHAR_BIT)) {
+		return false;
+	}
+
+	const unsigned char *ptr = reinterpret_cast<const unsigned char *>(set);
+	size_t off = cpu / CHAR_BIT;
+	size_t mask = 1 << (cpu % CHAR_BIT);
+
+	return (ptr[off] & mask);
+}
+
+int __mlibc_cpu_count(const size_t setsize, const cpu_set_t *set) {
+	size_t count = 0;
+	const unsigned char *ptr = reinterpret_cast<const unsigned char *>(set);
+
+	for(size_t i = 0; i < setsize; i++) {
+		for(size_t bit = 0; bit < CHAR_BIT; bit++) {
+			if((1 << bit) & ptr[i])
+				count++;
+		}
+	}
+
+	return count;
+}