[PATCH v17 03/14] util/cutils: refactor do_strtosz() to support suffixes list

[Tao Xu]

Add do_strtomul() to convert string according to different suffixes.

Reviewed-by: Eduardo Habkost <address@hidden>
Signed-off-by: Tao Xu <address@hidden>
---

No changes in v17.

Changes in v15:
    - Add a new patch to refactor do_strtosz() (Eduardo)
---
 util/cutils.c | 72 ++++++++++++++++++++++++++++++---------------------
 1 file changed, 42 insertions(+), 30 deletions(-)

diff --git a/util/cutils.c b/util/cutils.c
index d94a468954..ffef92338a 100644
--- a/util/cutils.c
+++ b/util/cutils.c
@@ -181,41 +181,37 @@ int fcntl_setfl(int fd, int flag)
 }
 #endif
 
-static int64_t suffix_mul(char suffix, int64_t unit)
+static int64_t suffix_mul(const char *suffixes[], int num_suffix,
+                          const char *endptr, int *offset, int64_t unit)
 {
-    switch (qemu_toupper(suffix)) {
-    case 'B':
-        return 1;
-    case 'K':
-        return unit;
-    case 'M':
-        return unit * unit;
-    case 'G':
-        return unit * unit * unit;
-    case 'T':
-        return unit * unit * unit * unit;
-    case 'P':
-        return unit * unit * unit * unit * unit;
-    case 'E':
-        return unit * unit * unit * unit * unit * unit;
+    int i, suffix_len;
+    int64_t mul = 1;
+
+    for (i = 0; i < num_suffix; i++) {
+        suffix_len = strlen(suffixes[i]);
+        if (g_ascii_strncasecmp(suffixes[i], endptr, suffix_len) == 0) {
+            *offset = suffix_len;
+            return mul;
+    }
+        mul *= unit;
     }
+
     return -1;
 }
 
 /*
- * Convert string to bytes, allowing either B/b for bytes, K/k for KB,
- * M/m for MB, G/g for GB or T/t for TB. End pointer will be returned
- * in *end, if not NULL. Return -ERANGE on overflow, and -EINVAL on
- * other error.
+ * Convert string according to different suffixes. End pointer will be returned
+ * in *end, if not NULL. Return -ERANGE on overflow, and -EINVAL on other 
error.
  */
-static int do_strtosz(const char *nptr, const char **end,
-                      const char default_suffix, int64_t unit,
+static int do_strtomul(const char *nptr, const char **end,
+                       const char *suffixes[], int num_suffix,
+                       const char *default_suffix, int64_t unit,
                       uint64_t *result)
 {
     int retval;
     const char *endptr;
-    unsigned char c;
     int mul_required = 0;
+    int offset = 0;
     long double val, mul, integral, fraction;
 
     retval = qemu_strtold_finite(nptr, &endptr, &val);
@@ -226,12 +222,12 @@ static int do_strtosz(const char *nptr, const char **end,
     if (fraction != 0) {
         mul_required = 1;
     }
-    c = *endptr;
-    mul = suffix_mul(c, unit);
+
+    mul = suffix_mul(suffixes, num_suffix, endptr, &offset, unit);
     if (mul >= 0) {
-        endptr++;
+        endptr += offset;
     } else {
-        mul = suffix_mul(default_suffix, unit);
+        mul = suffix_mul(suffixes, num_suffix, default_suffix, &offset, unit);
         assert(mul >= 0);
     }
     if (mul == 1 && mul_required) {
@@ -256,19 +252,35 @@ out:
     return retval;
 }
 
+/*
+ * Convert string to bytes, allowing either B/b for bytes, K/k for KB,
+ * M/m for MB, G/g for GB or T/t for TB. End pointer will be returned
+ * in *end, if not NULL. Return -ERANGE on overflow, and -EINVAL on
+ * other error.
+ */
+static int do_strtosz(const char *nptr, const char **end,
+                      const char *default_suffix, int64_t unit,
+                      uint64_t *result)
+{
+    static const char *suffixes[] = { "B", "K", "M", "G", "T", "P", "E" };
+
+    return do_strtomul(nptr, end, suffixes, ARRAY_SIZE(suffixes),
+                       default_suffix, unit, result);
+}
+
 int qemu_strtosz(const char *nptr, const char **end, uint64_t *result)
 {
-    return do_strtosz(nptr, end, 'B', 1024, result);
+    return do_strtosz(nptr, end, "B", 1024, result);
 }
 
 int qemu_strtosz_MiB(const char *nptr, const char **end, uint64_t *result)
 {
-    return do_strtosz(nptr, end, 'M', 1024, result);
+    return do_strtosz(nptr, end, "M", 1024, result);
 }
 
 int qemu_strtosz_metric(const char *nptr, const char **end, uint64_t *result)
 {
-    return do_strtosz(nptr, end, 'B', 1000, result);
+    return do_strtosz(nptr, end, "B", 1000, result);
 }
 
 /**
-- 
2.20.1