From: Bartosz Golaszewski <bartekgola@gmail.com>
Date: Sun, 5 Nov 2017 19:57:25 +0000 (+0100)
Subject: iter: rework line iterator API
X-Git-Url: http://git.maquefel.me/?a=commitdiff_plain;h=dfe98084e2641d49eed7d8d5203089031a819632;p=qemu-gpiodev%2Flibgpiod.git
iter: rework line iterator API
The changes roughly correspond with what we did for chip iterators.
Only perform operations that can fail in gpiod_line_iter_new(), so
that there's no need to check for errors after every call to
gpiod_line_iter_next().
Make gpiod_line_iter an opaque pointer and provide 'new' and 'free'
functions.
Update all users and relevant test cases. Extend the test API with
a new cleanup function.
Signed-off-by: Bartosz Golaszewski <bartekgola@gmail.com>
---
diff --git a/include/gpiod.h b/include/gpiod.h
index 8c0ec91..0039cda 100644
--- a/include/gpiod.h
+++ b/include/gpiod.h
@@ -45,6 +45,7 @@ extern "C" {
struct gpiod_chip;
struct gpiod_line;
struct gpiod_chip_iter;
+struct gpiod_line_iter;
/**
* @defgroup __common__ Common helper macros
@@ -1229,98 +1230,28 @@ gpiod_chip_iter_next_noclose(struct gpiod_chip_iter *iter) GPIOD_API;
(chip) = gpiod_chip_iter_next_noclose(iter))
/**
- * @brief Possible states of a line iterator.
+ * @brief Create a new line iterator.
+ * @param chip Active gpiochip handle over whose lines we want to iterate.
+ * @return New line iterator or NULL if an error occurred.
*/
-enum {
- GPIOD_LINE_ITER_STATE_INIT = 0,
- /**< Line iterator is initiated or iterating over lines. */
- GPIOD_LINE_ITER_STATE_DONE,
- /**< Line iterator is done with all lines on this chip. */
- GPIOD_LINE_ITER_STATE_ERR,
- /**< There was an error retrieving info for a line. */
-};
-
-/**
- * @brief GPIO line iterator structure.
- *
- * This structure is used in conjunction with gpiod_line_iter_next() to
- * iterate over all GPIO lines of a single GPIO chip.
- */
-struct gpiod_line_iter {
- unsigned int offset;
- /**< Current line offset. */
- struct gpiod_chip *chip;
- /**< GPIO chip whose line we're iterating over. */
- int state;
- /**< Current state of the iterator. */
-};
-
-/**
- * @brief Static initializer for line iterators.
- * @param chip The gpiochip object whose lines we want to iterate over.
- */
-#define GPIOD_LINE_ITER_INITIALIZER(chip) \
- { 0, (chip), GPIOD_LINE_ITER_STATE_INIT }
+struct gpiod_line_iter *
+gpiod_line_iter_new(struct gpiod_chip *chip) GPIOD_API;
/**
- * @brief Initialize a GPIO line iterator.
- * @param iter Pointer to a GPIO line iterator.
- * @param chip The gpiochip object whose lines we want to iterate over.
+ * @brief Free all resources associated with a GPIO line iterator.
+ * @param iter Line iterator object.
*/
-static inline void gpiod_line_iter_init(struct gpiod_line_iter *iter,
- struct gpiod_chip *chip)
-{
- iter->offset = 0;
- iter->chip = chip;
- iter->state = GPIOD_LINE_ITER_STATE_INIT;
-}
+void gpiod_line_iter_free(struct gpiod_line_iter *iter) GPIOD_API;
/**
* @brief Get the next GPIO line handle.
* @param iter The GPIO line iterator object.
- * @return Pointer to the next GPIO line handle or NULL if no more lines or
- * and error occured.
+ * @return Pointer to the next GPIO line handle or NULL there are no more
+ * lines left.
*/
struct gpiod_line *
gpiod_line_iter_next(struct gpiod_line_iter *iter) GPIOD_API;
-/**
- * @brief Check if we're done iterating over lines on this iterator.
- * @param iter The GPIO line iterator object.
- * @return True if we've iterated over all lines, false otherwise.
- */
-static inline bool gpiod_line_iter_done(const struct gpiod_line_iter *iter)
-{
- return iter->state == GPIOD_LINE_ITER_STATE_DONE;
-}
-
-/**
- * @brief Check if we've encountered an error condition while retrieving
- * info for a line.
- * @param iter The GPIO line iterator object.
- * @return True if there was an error retrieving info about a GPIO line,
- * false otherwise.
- */
-static inline bool gpiod_line_iter_err(const struct gpiod_line_iter *iter)
-{
- return iter->state == GPIOD_LINE_ITER_STATE_ERR;
-}
-
-/**
- * @brief Get the offset of the last line we tried to open.
- * @param iter The GPIO line iterator object.
- * @return The offset of the last line we tried to open - whether we failed
- * or succeeded to do so.
- *
- * If this function is called before gpiod_line_iter_next() is called at least
- * once, the results are undefined.
- */
-static inline unsigned int
-gpiod_line_iter_last_offset(const struct gpiod_line_iter *iter)
-{
- return iter->offset - 1;
-}
-
/**
* @brief Iterate over all GPIO lines of a single chip.
* @param iter An initialized GPIO line iterator.
@@ -1329,7 +1260,7 @@ gpiod_line_iter_last_offset(const struct gpiod_line_iter *iter)
*/
#define gpiod_foreach_line(iter, line) \
for ((line) = gpiod_line_iter_next(iter); \
- !gpiod_line_iter_done(iter); \
+ (line); \
(line) = gpiod_line_iter_next(iter))
/**
diff --git a/src/lib/helpers.c b/src/lib/helpers.c
index 085f44e..3b0bcf9 100644
--- a/src/lib/helpers.c
+++ b/src/lib/helpers.c
@@ -104,21 +104,24 @@ struct gpiod_chip * gpiod_chip_open_lookup(const char *descr)
struct gpiod_line *
gpiod_chip_find_line(struct gpiod_chip *chip, const char *name)
{
- struct gpiod_line_iter iter;
+ struct gpiod_line_iter *iter;
struct gpiod_line *line;
const char *tmp;
- gpiod_line_iter_init(&iter, chip);
- gpiod_foreach_line(&iter, line) {
- if (gpiod_line_iter_err(&iter))
- return NULL;
+ iter = gpiod_line_iter_new(chip);
+ if (!iter)
+ return NULL;
+ gpiod_foreach_line(iter, line) {
tmp = gpiod_line_name(line);
- if (tmp && strcmp(tmp, name) == 0)
+ if (tmp && strcmp(tmp, name) == 0) {
+ gpiod_line_iter_free(iter);
return line;
+ }
}
errno = ENOENT;
+ gpiod_line_iter_free(iter);
return NULL;
}
diff --git a/src/lib/iter.c b/src/lib/iter.c
index c6fdbaf..62a4165 100644
--- a/src/lib/iter.c
+++ b/src/lib/iter.c
@@ -21,6 +21,12 @@ struct gpiod_chip_iter {
unsigned int offset;
};
+struct gpiod_line_iter {
+ struct gpiod_line **lines;
+ unsigned int num_lines;
+ unsigned int offset;
+};
+
static int dir_filter(const struct dirent *dir)
{
return !strncmp(dir->d_name, "gpiochip", 8);
@@ -122,19 +128,44 @@ struct gpiod_chip * gpiod_chip_iter_next_noclose(struct gpiod_chip_iter *iter)
? iter->chips[iter->offset++] : NULL;
}
-struct gpiod_line * gpiod_line_iter_next(struct gpiod_line_iter *iter)
+struct gpiod_line_iter * gpiod_line_iter_new(struct gpiod_chip *chip)
{
- struct gpiod_line *line;
+ struct gpiod_line_iter *iter;
+ unsigned int i;
+
+ iter = malloc(sizeof(*iter));
+ if (!iter)
+ return NULL;
+
+ iter->num_lines = gpiod_chip_num_lines(chip);
+ iter->offset = 0;
- if (iter->offset >= gpiod_chip_num_lines(iter->chip)) {
- iter->state = GPIOD_LINE_ITER_STATE_DONE;
+ iter->lines = calloc(iter->num_lines, sizeof(*iter->lines));
+ if (!iter->lines) {
+ free(iter);
return NULL;
}
- iter->state = GPIOD_LINE_ITER_STATE_INIT;
- line = gpiod_chip_get_line(iter->chip, iter->offset++);
- if (!line)
- iter->state = GPIOD_LINE_ITER_STATE_ERR;
+ for (i = 0; i < iter->num_lines; i++) {
+ iter->lines[i] = gpiod_chip_get_line(chip, i);
+ if (!iter->lines[i]) {
+ free(iter->lines);
+ free(iter);
+ return NULL;
+ }
+ }
+
+ return iter;
+}
+
+void gpiod_line_iter_free(struct gpiod_line_iter *iter)
+{
+ free(iter->lines);
+ free(iter);
+}
- return line;
+struct gpiod_line * gpiod_line_iter_next(struct gpiod_line_iter *iter)
+{
+ return iter->offset < (iter->num_lines)
+ ? iter->lines[iter->offset++] : NULL;
}
diff --git a/src/tools/gpioinfo.c b/src/tools/gpioinfo.c
index 9bf940c..4a13ec1 100644
--- a/src/tools/gpioinfo.c
+++ b/src/tools/gpioinfo.c
@@ -88,22 +88,21 @@ static PRINTF(3, 4) void prinfo(bool *of,
static void list_lines(struct gpiod_chip *chip)
{
+ struct gpiod_line_iter *iter;
int direction, active_state;
- struct gpiod_line_iter iter;
const char *name, *consumer;
struct gpiod_line *line;
unsigned int i, offset;
bool flag_printed, of;
+ iter = gpiod_line_iter_new(chip);
+ if (!iter)
+ die_perror("error creating line iterator");
+
printf("%s - %u lines:\n",
gpiod_chip_name(chip), gpiod_chip_num_lines(chip));
- gpiod_line_iter_init(&iter, chip);
- gpiod_foreach_line(&iter, line) {
- if (gpiod_line_iter_err(&iter))
- die_perror("error retrieving info for line %u",
- gpiod_line_iter_last_offset(&iter));
-
+ gpiod_foreach_line(iter, line) {
offset = gpiod_line_offset(line);
name = gpiod_line_name(line);
consumer = gpiod_line_consumer(line);
@@ -147,6 +146,8 @@ static void list_lines(struct gpiod_chip *chip)
printf("\n");
}
+
+ gpiod_line_iter_free(iter);
}
int main(int argc, char **argv)
diff --git a/tests/gpiod-test.c b/tests/gpiod-test.c
index d64a24d..0c68e8c 100644
--- a/tests/gpiod-test.c
+++ b/tests/gpiod-test.c
@@ -1043,6 +1043,12 @@ void test_free_chip_iter(struct gpiod_chip_iter **iter)
gpiod_chip_iter_free(*iter);
}
+void test_free_line_iter(struct gpiod_line_iter **iter)
+{
+ if (*iter)
+ gpiod_line_iter_free(*iter);
+}
+
void test_free_chip_iter_noclose(struct gpiod_chip_iter **iter)
{
if (*iter)
diff --git a/tests/gpiod-test.h b/tests/gpiod-test.h
index 0f45188..44cabff 100644
--- a/tests/gpiod-test.h
+++ b/tests/gpiod-test.h
@@ -130,6 +130,7 @@ void test_line_close_chip(struct gpiod_line **line);
void test_free_str(char **str);
void test_free_chip_iter(struct gpiod_chip_iter **iter);
void test_free_chip_iter_noclose(struct gpiod_chip_iter **iter);
+void test_free_line_iter(struct gpiod_line_iter **iter);
bool test_regex_match(const char *str, const char *pattern);
diff --git a/tests/tests-iter.c b/tests/tests-iter.c
index 4555fa4..3b7039c 100644
--- a/tests/tests-iter.c
+++ b/tests/tests-iter.c
@@ -116,18 +116,18 @@ TEST_DEFINE(chip_iter_break,
static void line_iter(void)
{
+ TEST_CLEANUP(test_free_line_iter) struct gpiod_line_iter *iter = NULL;
TEST_CLEANUP(test_close_chip) struct gpiod_chip *chip = NULL;
- struct gpiod_line_iter iter;
struct gpiod_line *line;
unsigned int i = 0;
chip = gpiod_chip_open(test_chip_path(0));
TEST_ASSERT_NOT_NULL(chip);
- gpiod_line_iter_init(&iter, chip);
+ iter = gpiod_line_iter_new(chip);
+ TEST_ASSERT_NOT_NULL(iter);
- gpiod_foreach_line(&iter, line) {
- TEST_ASSERT(!gpiod_line_iter_err(&iter));
+ gpiod_foreach_line(iter, line) {
TEST_ASSERT_EQ(i, gpiod_line_offset(line));
i++;
}
@@ -137,28 +137,3 @@ static void line_iter(void)
TEST_DEFINE(line_iter,
"gpiod_line_iter - simple loop, check offsets",
0, { 8 });
-
-static void line_iter_static_initializer(void)
-{
- TEST_CLEANUP(test_close_chip) struct gpiod_chip *chip = NULL;
- struct gpiod_line *line;
- unsigned int i = 0;
-
- chip = gpiod_chip_open(test_chip_path(0));
- TEST_ASSERT_NOT_NULL(chip);
-
- {
- struct gpiod_line_iter iter = GPIOD_LINE_ITER_INITIALIZER(chip);
-
- gpiod_foreach_line(&iter, line) {
- TEST_ASSERT(!gpiod_line_iter_err(&iter));
- TEST_ASSERT_EQ(i, gpiod_line_offset(line));
- i++;
- }
- }
-
- TEST_ASSERT_EQ(8, i);
-}
-TEST_DEFINE(line_iter_static_initializer,
- "gpiod_line_iter - simple loop, static initializer",
- 0, { 8 });