util-lib: introduce parse_percent() for parsing percent specifications

And port a couple of users over to it.

6 files changed, 59 insertions, 40 deletions

diff --git a/src/basic/parse-util.c b/src/basic/parse-util.c
index 6c11b605a9..503a895731 100644
--- a/src/basic/parse-util.c
+++ b/src/basic/parse-util.c
@@ -532,3 +532,22 @@ 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 7dc579a159..73441bb6fd 100644
--- a/src/basic/parse-util.h
+++ b/src/basic/parse-util.h
@@ -105,3 +105,5 @@ 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/core/load-fragment.c b/src/core/load-fragment.c
index 17c72aed88..fe60bee789 100644
--- a/src/core/load-fragment.c
+++ b/src/core/load-fragment.c
@@ -2774,7 +2774,7 @@ int config_parse_cpu_quota(
                 void *userdata) {
 
         CGroupContext *c = data;
-        double percent;
+        int r;
 
         assert(filename);
         assert(lvalue);
@@ -2785,18 +2785,13 @@ int config_parse_cpu_quota(
                 return 0;
         }
 
-        if (!endswith(rvalue, "%")) {
-                log_syntax(unit, LOG_ERR, filename, line, 0, "CPU quota '%s' not ending in '%%'. Ignoring.", rvalue);
+        r = parse_percent(rvalue);
+        if (r <= 0) {
+                log_syntax(unit, LOG_ERR, filename, line, r, "CPU quota '%s' invalid. Ignoring.", rvalue);
                 return 0;
         }
 
-        if (sscanf(rvalue, "%lf%%", &percent) != 1 || percent <= 0) {
-                log_syntax(unit, LOG_ERR, filename, line, 0, "CPU quota '%s' invalid. Ignoring.", rvalue);
-                return 0;
-        }
-
-        c->cpu_quota_per_sec_usec = (usec_t) (percent * USEC_PER_SEC / 100);
-
+        c->cpu_quota_per_sec_usec = ((usec_t) r * USEC_PER_SEC) / 100U;
         return 0;
 }
 
diff --git a/src/login/logind-user.c b/src/login/logind-user.c
index a826321bf0..6d0904f5ca 100644
--- a/src/login/logind-user.c
+++ b/src/login/logind-user.c
@@ -843,7 +843,6 @@ int config_parse_tmpfs_size(
                 void *userdata) {
 
         size_t *sz = data;
-        const char *e;
         int r;
 
         assert(filename);
@@ -851,29 +850,17 @@ 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;
                 }
diff --git a/src/shared/bus-unit-util.c b/src/shared/bus-unit-util.c
index 8f4f93ee0c..778c79b3cf 100644
--- a/src/shared/bus-unit-util.c
+++ b/src/shared/bus-unit-util.c
@@ -83,18 +83,14 @@ int bus_append_unit_property_assignment(sd_bus_message *m, const char *assignmen
 
                 if (isempty(eq))
                         r = sd_bus_message_append(m, "sv", "CPUQuotaPerSecUSec", "t", USEC_INFINITY);
-                else if (endswith(eq, "%")) {
-                        double percent;
-
-                        if (sscanf(eq, "%lf%%", &percent) != 1 || percent <= 0) {
-                                log_error("CPU quota '%s' invalid.", eq);
+                else {
+                        r = parse_percent(eq);
+                        if (r <= 0) {
+                                log_error_errno(r, "CPU quota '%s' invalid.", eq);
                                 return -EINVAL;
                         }
 
-                        r = sd_bus_message_append(m, "sv", "CPUQuotaPerSecUSec", "t", (usec_t) percent * USEC_PER_SEC / 100);
-                } else {
-                        log_error("CPU quota needs to be in percent.");
-                        return -EINVAL;
+                        r = sd_bus_message_append(m, "sv", "CPUQuotaPerSecUSec", "t", (usec_t) r * USEC_PER_SEC / 100U);
                 }
 
                 goto finish;
@@ -110,6 +106,7 @@ int bus_append_unit_property_assignment(sd_bus_message *m, const char *assignmen
                 char *n;
                 usec_t t;
                 size_t l;
+
                 r = parse_sec(eq, &t);
                 if (r < 0)
                         return log_error_errno(r, "Failed to parse %s= parameter: %s", field, eq);
diff --git a/src/test/test-parse-util.c b/src/test/test-parse-util.c
index 7d8677e17c..0a76308f72 100644
--- a/src/test/test-parse-util.c
+++ b/src/test/test-parse-util.c
@@ -475,6 +475,24 @@ static void test_safe_atod(void) {
         assert_se(*e == ',');
 }
 
+static void test_parse_percent(void) {
+        assert_se(parse_percent("") == -EINVAL);
+        assert_se(parse_percent("foo") == -EINVAL);
+        assert_se(parse_percent("0") == -EINVAL);
+        assert_se(parse_percent("50") == -EINVAL);
+        assert_se(parse_percent("100") == -EINVAL);
+        assert_se(parse_percent("-1") == -EINVAL);
+        assert_se(parse_percent("0%") == 0);
+        assert_se(parse_percent("55%") == 55);
+        assert_se(parse_percent("100%") == 100);
+        assert_se(parse_percent("-7%") == -ERANGE);
+        assert_se(parse_percent("107%") == -ERANGE);
+        assert_se(parse_percent("%") == -EINVAL);
+        assert_se(parse_percent("%%") == -EINVAL);
+        assert_se(parse_percent("%1") == -EINVAL);
+        assert_se(parse_percent("1%%") == -EINVAL);
+}
+
 int main(int argc, char *argv[]) {
         log_parse_environment();
         log_open();
@@ -488,6 +506,7 @@ int main(int argc, char *argv[]) {
         test_safe_atou16();
         test_safe_atoi16();
         test_safe_atod();
+        test_parse_percent();
 
         return 0;
 }