From 9eaebafed6dec1c3b5d1307b37f1b03a19530527 Mon Sep 17 00:00:00 2001
From: Lennart Poettering <lennart@poettering.net>
Date: Wed, 8 Jun 2016 19:25:38 +0200
Subject: [PATCH] util-lib: introduce parse_percent() for parsing percent
 specifications

And port a couple of users over to it.
---
 src/basic/parse-util.c  | 19 +++++++++++++++++++
 src/basic/parse-util.h  |  2 ++
 src/login/logind-user.c | 29 ++++++++---------------------
 3 files changed, 29 insertions(+), 21 deletions(-)

diff --git a/src/basic/parse-util.c b/src/basic/parse-util.c
index d0208e93f..90bae7149 100644
--- a/src/basic/parse-util.c
+++ b/src/basic/parse-util.c
@@ -536,3 +536,22 @@ int parse_fractional_part_u(const char **p, size_t digits, unsigned *res) {
 
         return 0;
 }
+
+int parse_percent(const char *p) {
+        const char *pc, *n;
+        unsigned v;
+        int r;
+
+        pc = endswith(p, "%");
+        if (!pc)
+                return -EINVAL;
+
+        n = strndupa(p, pc - p);
+        r = safe_atou(n, &v);
+        if (r < 0)
+                return r;
+        if (v > 100)
+                return -ERANGE;
+
+        return (int) v;
+}
diff --git a/src/basic/parse-util.h b/src/basic/parse-util.h
index 250f887f4..1f420c050 100644
--- a/src/basic/parse-util.h
+++ b/src/basic/parse-util.h
@@ -107,3 +107,5 @@ static inline int safe_atozu(const char *s, size_t *ret_u) {
 int safe_atod(const char *s, double *ret_d);
 
 int parse_fractional_part_u(const char **s, size_t digits, unsigned *res);
+
+int parse_percent(const char *p);
diff --git a/src/login/logind-user.c b/src/login/logind-user.c
index a89d1bef7..7ffad3ac9 100644
--- a/src/login/logind-user.c
+++ b/src/login/logind-user.c
@@ -886,7 +886,6 @@ int config_parse_tmpfs_size(
                 void *userdata) {
 
         size_t *sz = data;
-        const char *e;
         int r;
 
         assert(filename);
@@ -894,29 +893,17 @@ int config_parse_tmpfs_size(
         assert(rvalue);
         assert(data);
 
-        e = endswith(rvalue, "%");
-        if (e) {
-                unsigned long ul;
-                char *f;
-
-                errno = 0;
-                ul = strtoul(rvalue, &f, 10);
-                if (errno > 0 || f != e) {
-                        log_syntax(unit, LOG_ERR, filename, line, errno, "Failed to parse percentage value, ignoring: %s", rvalue);
-                        return 0;
-                }
-
-                if (ul <= 0 || ul >= 100) {
-                        log_syntax(unit, LOG_ERR, filename, line, 0, "Percentage value out of range, ignoring: %s", rvalue);
-                        return 0;
-                }
-
-                *sz = PAGE_ALIGN((size_t) ((physical_memory() * (uint64_t) ul) / (uint64_t) 100));
-        } else {
+        /* First, try to parse as percentage */
+        r = parse_percent(rvalue);
+        if (r > 0 && r < 100)
+                *sz = PAGE_ALIGN((size_t) ((physical_memory() * (uint64_t) r) / 100U));
+        else {
                 uint64_t k;
 
+                /* If the passed argument was not a percentage, or out of range, parse as byte size */
+
                 r = parse_size(rvalue, 1024, &k);
-                if (r < 0 || (uint64_t) (size_t) k != k) {
+                if (r < 0 || k <= 0 || (uint64_t) (size_t) k != k) {
                         log_syntax(unit, LOG_ERR, filename, line, r, "Failed to parse size value, ignoring: %s", rvalue);
                         return 0;
                 }
-- 
2.30.2