basic: split out cpu set specific APIs into cpu-set-util.[ch]

1 files changed, 105 insertions, 0 deletions

diff --git a/src/basic/cpu-set-util.c b/src/basic/cpu-set-util.c
new file mode 100644
index 0000000000..519583c167
--- /dev/null
+++ b/src/basic/cpu-set-util.c
@@ -0,0 +1,105 @@
+/*-*- Mode: C; c-basic-offset: 8; indent-tabs-mode: nil -*-*/
+
+/***
+  This file is part of systemd.
+
+  Copyright 2010-2015 Lennart Poettering
+  Copyright 2015 Filipe Brandenburger
+
+  systemd is free software; you can redistribute it and/or modify it
+  under the terms of the GNU Lesser General Public License as published by
+  the Free Software Foundation; either version 2.1 of the License, or
+  (at your option) any later version.
+
+  systemd is distributed in the hope that it will be useful, but
+  WITHOUT ANY WARRANTY; without even the implied warranty of
+  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+  Lesser General Public License for more details.
+
+  You should have received a copy of the GNU Lesser General Public License
+  along with systemd; If not, see <http://www.gnu.org/licenses/>.
+***/
+
+#include "util.h"
+#include "cpu-set-util.h"
+
+cpu_set_t* cpu_set_malloc(unsigned *ncpus) {
+        cpu_set_t *c;
+        unsigned n = 1024;
+
+        /* Allocates the cpuset in the right size */
+
+        for (;;) {
+                c = CPU_ALLOC(n);
+                if (!c)
+                        return NULL;
+
+                if (sched_getaffinity(0, CPU_ALLOC_SIZE(n), c) >= 0) {
+                        CPU_ZERO_S(CPU_ALLOC_SIZE(n), c);
+
+                        if (ncpus)
+                                *ncpus = n;
+
+                        return c;
+                }
+
+                CPU_FREE(c);
+
+                if (errno != EINVAL)
+                        return NULL;
+
+                n *= 2;
+        }
+}
+
+int parse_cpu_set_and_warn(
+                const char *rvalue,
+                cpu_set_t **cpu_set,
+                const char *unit,
+                const char *filename,
+                unsigned line,
+                const char *lvalue) {
+
+        const char *whole_rvalue = rvalue;
+        _cleanup_cpu_free_ cpu_set_t *c = NULL;
+        unsigned ncpus = 0;
+
+        assert(lvalue);
+        assert(rvalue);
+
+        for (;;) {
+                _cleanup_free_ char *word = NULL;
+                unsigned cpu;
+                int r;
+
+                r = extract_first_word(&rvalue, &word, WHITESPACE, EXTRACT_QUOTES);
+                if (r < 0) {
+                        log_syntax(unit, LOG_ERR, filename, line, r, "Invalid value for %s: %s", lvalue, whole_rvalue);
+                        return r;
+                }
+                if (r == 0)
+                        break;
+
+                if (!c) {
+                        c = cpu_set_malloc(&ncpus);
+                        if (!c)
+                                return log_oom();
+                }
+
+                r = safe_atou(word, &cpu);
+                if (r < 0 || cpu >= ncpus) {
+                        log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse CPU affinity '%s'", rvalue);
+                        return -EINVAL;
+                }
+
+                CPU_SET_S(cpu, CPU_ALLOC_SIZE(ncpus), c);
+        }
+
+        /* On success, sets *cpu_set and returns ncpus for the system. */
+        if (c) {
+                *cpu_set = c;
+                c = NULL;
+        }
+
+        return (int) ncpus;
+}