versioncmp: factor out helper for suffix matching
As the number of identical steps to be done for both tagnames grows, extract them into a helper function, with the additional benefit that the conditionals near the end of swap_prereleases() will use more meaningful variable names. Signed-off-by: SZEDER Gábor <szeder.dev@gmail.com> Signed-off-by: Junio C Hamano <gitster@pobox.com>
SZEDER Gábor committed
Dec 8, 2016 at 15:48 UTC
b17846432da4f8530c7349561eac4a16f95bbd5b
1 file changed
+39
-25
versioncmp.c
+39
-25
@@ -24,6 +24,31 @@
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static const struct string_list *prereleases;
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static int initialized;
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+struct suffix_match {
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+ int conf_pos;
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+ int start;
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+ int len;
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+};
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+
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+static void find_better_matching_suffix(const char *tagname, const char *suffix,
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+ int suffix_len, int start, int conf_pos,
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+ struct suffix_match *match)
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+{
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+ /*
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+ * A better match either starts earlier or starts at the same offset
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+ * but is longer.
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+ */
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+ int end = match->len < suffix_len ? match->start : match->start-1;
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+ int i;
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+ for (i = start; i <= end; i++)
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+ if (starts_with(tagname + i, suffix)) {
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+ match->conf_pos = conf_pos;
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+ match->start = i;
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+ match->len = suffix_len;
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+ break;
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+ }
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+}
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+
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/*
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* off is the offset of the first different character in the two strings
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* s1 and s2. If either s1 or s2 contains a prerelease suffix containing
@@ -47,46 +72,35 @@ static int swap_prereleases(const char *s1,
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int off,
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int *diff)
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{
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- int i, i1 = -1, i2 = -1;
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- int start_at1 = off, start_at2 = off, match_len1 = -1, match_len2 = -1;
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+ int i;
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+ struct suffix_match match1 = { -1, off, -1 };
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+ struct suffix_match match2 = { -1, off, -1 };
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for (i = 0; i < prereleases->nr; i++) {
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const char *suffix = prereleases->items[i].string;
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- int j, start, end, suffix_len = strlen(suffix);
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+ int start, suffix_len = strlen(suffix);
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if (suffix_len < off)
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start = off - suffix_len;
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else
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start = 0;
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- end = match_len1 < suffix_len ? start_at1 : start_at1-1;
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- for (j = start; j <= end; j++)
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- if (starts_with(s1 + j, suffix)) {
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- i1 = i;
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- start_at1 = j;
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- match_len1 = suffix_len;
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- break;
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- }
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- end = match_len2 < suffix_len ? start_at2 : start_at2-1;
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- for (j = start; j <= end; j++)
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- if (starts_with(s2 + j, suffix)) {
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- i2 = i;
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- start_at2 = j;
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- match_len2 = suffix_len;
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- break;
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- }
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+ find_better_matching_suffix(s1, suffix, suffix_len, start,
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+ i, &match1);
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+ find_better_matching_suffix(s2, suffix, suffix_len, start,
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+ i, &match2);
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}
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- if (i1 == -1 && i2 == -1)
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+ if (match1.conf_pos == -1 && match2.conf_pos == -1)
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return 0;
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- if (i1 == i2)
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+ if (match1.conf_pos == match2.conf_pos)
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/* Found the same suffix in both, e.g. "-rc" in "v1.0-rcX"
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* and "v1.0-rcY": the caller should decide based on "X"
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* and "Y". */
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return 0;
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- if (i1 >= 0 && i2 >= 0)
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- *diff = i1 - i2;
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- else if (i1 >= 0)
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+ if (match1.conf_pos >= 0 && match2.conf_pos >= 0)
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+ *diff = match1.conf_pos - match2.conf_pos;
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+ else if (match1.conf_pos >= 0)
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*diff = -1;
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- else /* if (i2 >= 0) */
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+ else /* if (match2.conf_pos >= 0) */
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*diff = 1;
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return 1;
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}