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[PATCH v5 06/10] config API: don't lose the git_*get*() return values

From
Ævar Arnfjörð Bjarmason <avarab@gmail.com>
Date
Feb 7, 2023, 16:10 UTC
Message-ID
<patch-v5-06.10-b515ff13f9b-20230207T154000Z-avarab@gmail.com>
In-Reply-To
<cover-v5-00.10-00000000000-20230207T154000Z-avarab@gmail.com>

Since a preceding commit which added the "git_config_get()" family of functions, and the preceding commit where *_multi() started returning an "int" we've finally been able to ferry up non-zero return values, rather than having negative return values normalized to a "return 1" along the way.

In practice this doesn't matter to existing callers. They're either ignoring these return values and relying on us to only populate "dest" if we'd return 0, or normalizing non-zero return values with "!".

Even if they weren't normalizing them we'll only return non-zero negative values in those cases where the config key itself is bad, which excludes the vast majority of our callers, as they hardcode a valued configuration key as a fixed string in the C sources.

So this change is expected to do nothing for now, but is really here for our own sanity. It's much harder to reason about an API that's losing return values in some cases, and coercing them in others. If there isn't a compelling reason to do otherwise we should let the caller decide if they care about the distinction between bad keys and non-existence.

Signed-off-by: Ævar Arnfjörð Bjarmason <avarab@gmail.com>
---
 config.c | 117 ++++++++++++++++++++++++++++++-------------------------
 config.h |  16 ++++----
 2 files changed, 72 insertions(+), 61 deletions(-)
diff --git a/config.c b/config.c
index 569819b4a1b..8d7e40ac8a4 100644
--- a/config.c
+++ b/config.c
@@ -2463,86 +2463,93 @@ int git_configset_get(struct config_set *cs, const char *key)
 int git_configset_get_string(struct config_set *cs, const char *key, char **dest)
 {
 	const char *value;
-	if (!git_configset_get_value(cs, key, &value))
-		return git_config_string((const char **)dest, key, value);
-	else
-		return 1;
+	int ret;
+
+	if ((ret = git_configset_get_value(cs, key, &value)))
+		return ret;
+	return git_config_string((const char **)dest, key, value);
 }
 
 static int git_configset_get_string_tmp(struct config_set *cs, const char *key,
 					const char **dest)
 {
 	const char *value;
-	if (!git_configset_get_value(cs, key, &value)) {
-		if (!value)
-			return config_error_nonbool(key);
-		*dest = value;
-		return 0;
-	} else {
-		return 1;
-	}
+	int ret;
+
+	if ((ret = git_configset_get_value(cs, key, &value)))
+		return ret;
+	if (!value)
+		return config_error_nonbool(key);
+	*dest = value;
+	return 0;
 }
 
 int git_configset_get_int(struct config_set *cs, const char *key, int *dest)
 {
 	const char *value;
-	if (!git_configset_get_value(cs, key, &value)) {
-		*dest = git_config_int(key, value);
-		return 0;
-	} else
-		return 1;
+	int ret;
+
+	if ((ret = git_configset_get_value(cs, key, &value)))
+		return ret;
+	*dest = git_config_int(key, value);
+	return 0;
 }
 
 int git_configset_get_ulong(struct config_set *cs, const char *key, unsigned long *dest)
 {
 	const char *value;
-	if (!git_configset_get_value(cs, key, &value)) {
-		*dest = git_config_ulong(key, value);
-		return 0;
-	} else
-		return 1;
+	int ret;
+
+	if ((ret = git_configset_get_value(cs, key, &value)))
+		return ret;
+	*dest = git_config_ulong(key, value);
+	return 0;
 }
 
 int git_configset_get_bool(struct config_set *cs, const char *key, int *dest)
 {
 	const char *value;
-	if (!git_configset_get_value(cs, key, &value)) {
-		*dest = git_config_bool(key, value);
-		return 0;
-	} else
-		return 1;
+	int ret;
+
+	if ((ret = git_configset_get_value(cs, key, &value)))
+		return ret;
+	*dest = git_config_bool(key, value);
+	return 0;
 }
 
 int git_configset_get_bool_or_int(struct config_set *cs, const char *key,
 				int *is_bool, int *dest)
 {
 	const char *value;
-	if (!git_configset_get_value(cs, key, &value)) {
-		*dest = git_config_bool_or_int(key, value, is_bool);
-		return 0;
-	} else
-		return 1;
+	int ret;
+
+	if ((ret = git_configset_get_value(cs, key, &value)))
+		return ret;
+	*dest = git_config_bool_or_int(key, value, is_bool);
+	return 0;
 }
 
 int git_configset_get_maybe_bool(struct config_set *cs, const char *key, int *dest)
 {
 	const char *value;
-	if (!git_configset_get_value(cs, key, &value)) {
-		*dest = git_parse_maybe_bool(value);
-		if (*dest == -1)
-			return -1;
-		return 0;
-	} else
-		return 1;
+	int ret;
+
+	if ((ret = git_configset_get_value(cs, key, &value)))
+		return ret;
+	*dest = git_parse_maybe_bool(value);
+	if (*dest == -1)
+		return -1;
+	return 0;
 }
 
 int git_configset_get_pathname(struct config_set *cs, const char *key, const char **dest)
 {
 	const char *value;
-	if (!git_configset_get_value(cs, key, &value))
-		return git_config_pathname(dest, key, value);
-	else
-		return 1;
+	int ret;
+
+	if ((ret = git_configset_get_value(cs, key, &value)))
+		return ret;
+	return git_config_pathname(dest, key, value);
 }
 
 /* Functions use to read configuration from a repository */
@@ -2789,9 +2796,11 @@ int git_config_get_expiry_in_days(const char *key, timestamp_t *expiry, timestam
 	const char *expiry_string;
 	intmax_t days;
 	timestamp_t when;
+	int ret;
 
-	if (git_config_get_string_tmp(key, &expiry_string))
-		return 1; /* no such thing */
+	if ((ret = git_config_get_string_tmp(key, &expiry_string)))
+		/* no such thing, or git_config_parse_key() failure etc. */
+		return ret;
 
 	if (git_parse_signed(expiry_string, &days, maximum_signed_value_of_type(int))) {
 		const int scale = 86400;
@@ -2834,6 +2843,7 @@ int git_config_get_max_percent_split_change(void)
 int git_config_get_index_threads(int *dest)
 {
 	int is_bool, val;
+	int ret;
 
 	val = git_env_ulong("GIT_TEST_INDEX_THREADS", 0);
 	if (val) {
@@ -2841,15 +2851,14 @@ int git_config_get_index_threads(int *dest)
 		return 0;
 	}
 
-	if (!git_config_get_bool_or_int("index.threads", &is_bool, &val)) {
-		if (is_bool)
-			*dest = val ? 0 : 1;
-		else
-			*dest = val;
-		return 0;
-	}
-
-	return 1;
+	if ((ret = git_config_get_bool_or_int("index.threads", &is_bool,
+					      &val)))
+		return ret;
+	if (is_bool)
+		*dest = val ? 0 : 1;
+	else
+		*dest = val;
+	return 0;
 }
 
 NORETURN
diff --git a/config.h b/config.h
index 115259ecb8d..da5c498d39a 100644
--- a/config.h
+++ b/config.h
@@ -477,20 +477,22 @@ int git_configset_get_value_multi(struct config_set *cs, const char *key,
  */
 void git_configset_clear(struct config_set *cs);
 
-/*
+/**
  * These functions return 1 if not found, and 0 if found, leaving the found
- * value in the 'dest' pointer.
+ * value in the 'dest' pointer. On error a negative value is returned.
+ *
+ * The functions that return a single value (i.e. not
+ * *_get_*multi*()) will return the highest-priority value for the
+ * configuration variable `key`, i.e. in the case where we have
+ * multiple values the last value found.
  */
 
 RESULT_MUST_BE_USED
 int git_configset_get(struct config_set *cs, const char *key);
 
 /*
- * Finds the highest-priority value for the configuration variable `key`
- * and config set `cs`, stores the pointer to it in `value` and returns 0.
- * When the configuration variable `key` is not found, returns 1 without
- * touching `value`. The caller should not free or modify `value`, as it
- * is owned by the cache.
+ * The caller should not free or modify `value`, as it is owned by the
+ * cache.
  */
 int git_configset_get_value(struct config_set *cs, const char *key, const char **dest);
 
-- 
2.39.1.1430.gb2471c0aaf4
Previous: Ævar Arnfjörð BjarmasonNext: Ævar Arnfjörð Bjarmason
Message 89 of 134 in “config API: make "multi" safe, fix numerous segfaults”
  1. 00/10 config API: make "multi" safe, fix numerous segfaultsÆvar Arnfjörð Bjarmason, Oct 26, 2022
  2. 01/10 config API: have *_multi() return an "int" and take a "dest"Ævar Arnfjörð Bjarmason, Oct 26, 2022
  3. SZEDER GáborOct 26, 2022
  4. Ævar Arnfjörð BjarmasonOct 26, 2022
  5. Junio C HamanoOct 27, 2022
  6. 02/10 for-each-repo: error on bad --configÆvar Arnfjörð Bjarmason, Oct 26, 2022
  7. 03/10 config API: mark *_multi() with RESULT_MUST_BE_USEDÆvar Arnfjörð Bjarmason, Oct 26, 2022
  8. 04/10 string-list API: mark "struct_string_list" to "for_each_string_list" constÆvar Arnfjörð Bjarmason, Oct 26, 2022
  9. Junio C HamanoOct 27, 2022
  10. Ævar Arnfjörð BjarmasonOct 27, 2022
  11. 05/10 string-list API: make has_string() and list_lookup() "const"Ævar Arnfjörð Bjarmason, Oct 26, 2022
  12. 06/10 builtin/gc.c: use "unsorted_string_list_has_string()" where appropriateÆvar Arnfjörð Bjarmason, Oct 26, 2022
  13. Junio C HamanoOct 27, 2022
  14. Ævar Arnfjörð BjarmasonOct 27, 2022
  15. 08/10 config tests: add "NULL" tests for *_get_value_multi()Ævar Arnfjörð Bjarmason, Oct 26, 2022
  16. Junio C HamanoOct 27, 2022
  17. 07/10 config API: add and use "lookup_value" functionsÆvar Arnfjörð Bjarmason, Oct 26, 2022
  18. Junio C HamanoOct 27, 2022
  19. 10/10 for-each-repo: with bad config, don't conflate <path> and <cmd>Ævar Arnfjörð Bjarmason, Oct 26, 2022
  20. 09/10 config API: add "string" version of *_value_multi(), fix segfaultsÆvar Arnfjörð Bjarmason, Oct 26, 2022
  21. Junio C HamanoOct 27, 2022
  22. Junio C HamanoOct 27, 2022
  23. Ævar Arnfjörð BjarmasonOct 27, 2022
  24. Junio C HamanoOct 28, 2022
  25. Ævar Arnfjörð BjarmasonOct 31, 2022
  26. Junio C HamanoOct 27, 2022
  27. 0/9 config API: make "multi" safe, fix numerous segfaultsÆvar Arnfjörð Bjarmason, Nov 1, 2022
  28. 1/9 for-each-repo tests: test bad --config keysÆvar Arnfjörð Bjarmason, Nov 1, 2022
  29. 2/9 config tests: cover blind spots in git_die_config() testsÆvar Arnfjörð Bjarmason, Nov 1, 2022
  30. 3/9 config tests: add "NULL" tests for *_get_value_multi()Ævar Arnfjörð Bjarmason, Nov 1, 2022
  31. 4/9 versioncmp.c: refactor config reading next commitÆvar Arnfjörð Bjarmason, Nov 1, 2022
  32. 5/9 config API: have *_multi() return an "int" and take a "dest"Ævar Arnfjörð Bjarmason, Nov 1, 2022
  33. 7/9 config API users: test for *_get_value_multi() segfaultsÆvar Arnfjörð Bjarmason, Nov 1, 2022
  34. 6/9 for-each-repo: error on bad --configÆvar Arnfjörð Bjarmason, Nov 1, 2022
  35. 8/9 config API: add "string" version of *_value_multi(), fix segfaultsÆvar Arnfjörð Bjarmason, Nov 1, 2022
  36. 9/9 for-each-repo: with bad config, don't conflate <path> and <cmd>Ævar Arnfjörð Bjarmason, Nov 1, 2022
  37. Taylor BlauNov 2, 2022
  38. 0/9 config API: make "multi" safe, fix numerous segfaultsÆvar Arnfjörð Bjarmason, Nov 25, 2022
  39. 1/9 for-each-repo tests: test bad --config keysÆvar Arnfjörð Bjarmason, Nov 25, 2022
  40. 4/9 versioncmp.c: refactor config reading next commitÆvar Arnfjörð Bjarmason, Nov 25, 2022
  41. 3/9 config tests: add "NULL" tests for *_get_value_multi()Ævar Arnfjörð Bjarmason, Nov 25, 2022
  42. Glen ChooJan 19, 2023
  43. 2/9 config tests: cover blind spots in git_die_config() testsÆvar Arnfjörð Bjarmason, Nov 25, 2022
  44. Glen ChooJan 19, 2023
  45. 6/9 for-each-repo: error on bad --configÆvar Arnfjörð Bjarmason, Nov 25, 2022
  46. 5/9 config API: have *_multi() return an "int" and take a "dest"Ævar Arnfjörð Bjarmason, Nov 25, 2022
  47. Glen ChooJan 19, 2023
  48. 7/9 config API users: test for *_get_value_multi() segfaultsÆvar Arnfjörð Bjarmason, Nov 25, 2022
  49. Glen ChooJan 19, 2023
  50. 8/9 config API: add "string" version of *_value_multi(), fix segfaultsÆvar Arnfjörð Bjarmason, Nov 25, 2022
  51. Glen ChooJan 19, 2023
  52. 9/9 for-each-repo: with bad config, don't conflate <path> and <cmd>Ævar Arnfjörð Bjarmason, Nov 25, 2022
  53. Glen ChooJan 19, 2023
  54. 0/9 config API: make "multi" safe, fix numerous segfaultsÆvar Arnfjörð Bjarmason, Feb 2, 2023
  55. 1/9 config tests: cover blind spots in git_die_config() testsÆvar Arnfjörð Bjarmason, Feb 2, 2023
  56. Junio C HamanoFeb 3, 2023
  57. Glen ChooFeb 6, 2023
  58. 2/9 config tests: add "NULL" tests for *_get_value_multi()Ævar Arnfjörð Bjarmason, Feb 2, 2023
  59. Junio C HamanoFeb 2, 2023
  60. Glen ChooFeb 6, 2023
  61. Ævar Arnfjörð BjarmasonFeb 6, 2023
  62. Glen ChooFeb 6, 2023
  63. 4/9 versioncmp.c: refactor config reading next commitÆvar Arnfjörð Bjarmason, Feb 2, 2023
  64. Junio C HamanoFeb 3, 2023
  65. 3/9 config API: add and use a "git_config_get()" family of functionsÆvar Arnfjörð Bjarmason, Feb 2, 2023
  66. Junio C HamanoFeb 2, 2023
  67. Ævar Arnfjörð BjarmasonFeb 7, 2023
  68. Glen ChooFeb 6, 2023
  69. Glen ChooFeb 6, 2023
  70. Ævar Arnfjörð BjarmasonFeb 7, 2023
  71. 6/9 for-each-repo: error on bad --configÆvar Arnfjörð Bjarmason, Feb 2, 2023
  72. Glen ChooFeb 6, 2023
  73. 5/9 config API: have *_multi() return an "int" and take a "dest"Ævar Arnfjörð Bjarmason, Feb 2, 2023
  74. 7/9 config API users: test for *_get_value_multi() segfaultsÆvar Arnfjörð Bjarmason, Feb 2, 2023
  75. 9/9 for-each-repo: with bad config, don't conflate <path> and <cmd>Ævar Arnfjörð Bjarmason, Feb 2, 2023
  76. 8/9 config API: add "string" version of *_value_multi(), fix segfaultsÆvar Arnfjörð Bjarmason, Feb 2, 2023
  77. Glen ChooFeb 6, 2023
  78. 00/10 config API: make "multi" safe, fix segfaults, propagate "ret"Ævar Arnfjörð Bjarmason, Feb 7, 2023
  79. 01/10 config tests: cover blind spots in git_die_config() testsÆvar Arnfjörð Bjarmason, Feb 7, 2023
  80. 02/10 config tests: add "NULL" tests for *_get_value_multi()Ævar Arnfjörð Bjarmason, Feb 7, 2023
  81. Glen ChooFeb 9, 2023
  82. 04/10 versioncmp.c: refactor config reading next commitÆvar Arnfjörð Bjarmason, Feb 7, 2023
  83. 03/10 config API: add and use a "git_config_get()" family of functionsÆvar Arnfjörð Bjarmason, Feb 7, 2023
  84. Glen ChooFeb 9, 2023
  85. Ævar Arnfjörð BjarmasonFeb 9, 2023
  86. Ævar Arnfjörð BjarmasonFeb 9, 2023
  87. Glen ChooFeb 9, 2023
  88. 05/10 config API: have *_multi() return an "int" and take a "dest"Ævar Arnfjörð Bjarmason, Feb 7, 2023
  89. 06/10 config API: don't lose the git_*get*() return valuesÆvar Arnfjörð Bjarmason, Feb 7, 2023
  90. 07/10 for-each-repo: error on bad --configÆvar Arnfjörð Bjarmason, Feb 7, 2023
  91. 08/10 config API users: test for *_get_value_multi() segfaultsÆvar Arnfjörð Bjarmason, Feb 7, 2023
  92. 09/10 config API: add "string" version of *_value_multi(), fix segfaultsÆvar Arnfjörð Bjarmason, Feb 7, 2023
  93. 10/10 for-each-repo: with bad config, don't conflate <path> and <cmd>Ævar Arnfjörð Bjarmason, Feb 7, 2023
  94. Junio C HamanoFeb 7, 2023
  95. 0/9 config API: make "multi" safe, fix segfaults, propagate "ret"Ævar Arnfjörð Bjarmason, Mar 7, 2023
  96. 1/9 config tests: cover blind spots in git_die_config() testsÆvar Arnfjörð Bjarmason, Mar 7, 2023
  97. 4/9 versioncmp.c: refactor config reading next commitÆvar Arnfjörð Bjarmason, Mar 7, 2023
  98. 6/9 for-each-repo: error on bad --configÆvar Arnfjörð Bjarmason, Mar 7, 2023
  99. 3/9 config API: add and use a "git_config_get()" family of functionsÆvar Arnfjörð Bjarmason, Mar 7, 2023
  100. 5/9 config API: have *_multi() return an "int" and take a "dest"Ævar Arnfjörð Bjarmason, Mar 7, 2023
  101. 7/9 config API users: test for *_get_value_multi() segfaultsÆvar Arnfjörð Bjarmason, Mar 7, 2023
  102. 8/9 config API: add "string" version of *_value_multi(), fix segfaultsÆvar Arnfjörð Bjarmason, Mar 7, 2023
  103. 9/9 for-each-repo: with bad config, don't conflate <path> and <cmd>Ævar Arnfjörð Bjarmason, Mar 7, 2023
  104. 2/9 config tests: add "NULL" tests for *_get_value_multi()Ævar Arnfjörð Bjarmason, Mar 7, 2023
  105. Glen ChooMar 8, 2023
  106. 0/9 config API: make "multi" safe, fix segfaults, propagate "ret"Ævar Arnfjörð Bjarmason, Mar 8, 2023
  107. 1/9 config tests: cover blind spots in git_die_config() testsÆvar Arnfjörð Bjarmason, Mar 8, 2023
  108. 2/9 config tests: add "NULL" tests for *_get_value_multi()Ævar Arnfjörð Bjarmason, Mar 8, 2023
  109. 3/9 config API: add and use a "git_config_get()" family of functionsÆvar Arnfjörð Bjarmason, Mar 8, 2023
  110. Glen ChooMar 9, 2023
  111. Ævar Arnfjörð BjarmasonMar 14, 2023
  112. 4/9 versioncmp.c: refactor config reading next commitÆvar Arnfjörð Bjarmason, Mar 8, 2023
  113. 7/9 config API users: test for *_get_value_multi() segfaultsÆvar Arnfjörð Bjarmason, Mar 8, 2023
  114. 6/9 for-each-repo: error on bad --configÆvar Arnfjörð Bjarmason, Mar 8, 2023
  115. 8/9 config API: add "string" version of *_value_multi(), fix segfaultsÆvar Arnfjörð Bjarmason, Mar 8, 2023
  116. 9/9 for-each-repo: with bad config, don't conflate <path> and <cmd>Ævar Arnfjörð Bjarmason, Mar 8, 2023
  117. 5/9 config API: have *_multi() return an "int" and take a "dest"Ævar Arnfjörð Bjarmason, Mar 8, 2023
  118. Glen ChooMar 9, 2023
  119. Glen ChooMar 9, 2023
  120. Junio C HamanoMar 9, 2023
  121. 0/9 config API: make "multi" safe, fix segfaults, propagate "ret"Ævar Arnfjörð Bjarmason, Mar 28, 2023
  122. 1/9 config tests: cover blind spots in git_die_config() testsÆvar Arnfjörð Bjarmason, Mar 28, 2023
  123. 2/9 config tests: add "NULL" tests for *_get_value_multi()Ævar Arnfjörð Bjarmason, Mar 28, 2023
  124. 3/9 config API: add and use a "git_config_get()" family of functionsÆvar Arnfjörð Bjarmason, Mar 28, 2023
  125. 4/9 versioncmp.c: refactor config reading next commitÆvar Arnfjörð Bjarmason, Mar 28, 2023
  126. 5/9 config API: have *_multi() return an "int" and take a "dest"Ævar Arnfjörð Bjarmason, Mar 28, 2023
  127. 6/9 for-each-repo: error on bad --configÆvar Arnfjörð Bjarmason, Mar 28, 2023
  128. 8/9 config API: add "string" version of *_value_multi(), fix segfaultsÆvar Arnfjörð Bjarmason, Mar 28, 2023
  129. 7/9 config API users: test for *_get_value_multi() segfaultsÆvar Arnfjörð Bjarmason, Mar 28, 2023
  130. 9/9 for-each-repo: with bad config, don't conflate <path> and <cmd>Ævar Arnfjörð Bjarmason, Mar 28, 2023
  131. SZEDER GáborApr 7, 2023
  132. Glen ChooMar 28, 2023
  133. Junio C HamanoMar 28, 2023
  134. Junio C HamanoMar 29, 2023

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