</div>\r
<div id="preamble">\r
<div class="sectionbody">\r
-<p>Talk about <path-list.h>, things like</p>\r
+<p>The path_list API offers a data structure and functions to handle sorted\r
+and unsorted string lists.</p>\r
+<p>The name is a bit misleading, a path_list may store not only paths but\r
+strings in general.</p>\r
+<p>The caller:</p>\r
+<ol>\r
+<li>\r
+<p>\r
+Allocates and clears a <tt>struct path_list</tt> variable.\r
+</p>\r
+</li>\r
+<li>\r
+<p>\r
+Initializes the members. You might want to set the flag <tt>strdup_paths</tt>\r
+ if the strings should be strdup()ed. For example, this is necessary\r
+ when you add something like git_path("…"), since that function returns\r
+ a static buffer that will change with the next call to git_path().\r
+</p>\r
+<p>If you need something advanced, you can manually malloc() the <tt>items</tt>\r
+member (you need this if you add things later) and you should set the\r
+<tt>nr</tt> and <tt>alloc</tt> members in that case, too.</p>\r
+</li>\r
+<li>\r
+<p>\r
+Adds new items to the list, using <tt>path_list_append</tt> or <tt>path_list_insert</tt>.\r
+</p>\r
+</li>\r
+<li>\r
+<p>\r
+Can check if a string is in the list using <tt>path_list_has_path</tt> or\r
+ <tt>unsorted_path_list_has_path</tt> and get it from the list using\r
+ <tt>path_list_lookup</tt> for sorted lists.\r
+</p>\r
+</li>\r
+<li>\r
+<p>\r
+Can sort an unsorted list using <tt>sort_path_list</tt>.\r
+</p>\r
+</li>\r
+<li>\r
+<p>\r
+Finally it should free the list using <tt>path_list_clear</tt>.\r
+</p>\r
+</li>\r
+</ol>\r
+<p>Example:</p>\r
+<div class="listingblock">\r
+<div class="content">\r
+<pre><tt>struct path_list list;\r
+int i;\r
+\r
+memset(&list, 0, sizeof(struct path_list));\r
+path_list_append("foo", &list);\r
+path_list_append("bar", &list);\r
+for (i = 0; i < list.nr; i++)\r
+ printf("%s\n", list.items[i].path)</tt></pre>\r
+</div></div>\r
+<div class="admonitionblock">\r
+<table><tr>\r
+<td class="icon">\r
+<div class="title">Note</div>\r
+</td>\r
+<td class="content">It is more efficient to build an unsorted list and sort it\r
+afterwards, instead of building a sorted list (<tt>O(n log n)</tt> instead of\r
+<tt>O(n^2)</tt>).</td>\r
+</tr></table>\r
+</div>\r
+<p>+\r
+However, if you use the list to check if a certain string was added\r
+already, you should not do that (using unsorted_path_list_has_path()),\r
+because the complexity would be quadratic again (but with a worse factor).</p>\r
+</div>\r
+</div>\r
+<h2>Functions</h2>\r
+<div class="sectionbody">\r
<ul>\r
<li>\r
<p>\r
-it is not just paths but strings in general;\r
+General ones (works with sorted and unsorted lists as well)\r
+</p>\r
+<dl>\r
+<dt>\r
+<tt>print_path_list</tt>\r
+</dt>\r
+<dd>\r
+<p>\r
+ Dump a path_list to stdout, useful mainly for debugging purposes. It\r
+ can take an optional header argument and it writes out the\r
+ string-pointer pairs of the path_list, each one in its own line.\r
</p>\r
+</dd>\r
+<dt>\r
+<tt>path_list_clear</tt>\r
+</dt>\r
+<dd>\r
+<p>\r
+ Free a path_list. The <tt>path</tt> pointer of the items will be freed in case\r
+ the <tt>strdup_paths</tt> member of the path_list is set. The second parameter\r
+ controls if the <tt>util</tt> pointer of the items should be freed or not.\r
+</p>\r
+</dd>\r
+</dl>\r
</li>\r
<li>\r
<p>\r
-the calling sequence.\r
+Functions for sorted lists only\r
</p>\r
+<dl>\r
+<dt>\r
+<tt>path_list_has_path</tt>\r
+</dt>\r
+<dd>\r
+<p>\r
+ Determine if the path_list has a given string or not.\r
+</p>\r
+</dd>\r
+<dt>\r
+<tt>path_list_insert</tt>\r
+</dt>\r
+<dd>\r
+<p>\r
+ Insert a new element to the path_list. The returned pointer can be handy\r
+ if you want to write something to the <tt>util</tt> pointer of the\r
+ path_list_item containing the just added string.\r
+</p>\r
+<p>Since this function uses xrealloc() (which die()s if it fails) if the\r
+list needs to grow, it is safe not to check the pointer. I.e. you may\r
+write <tt>path_list_insert(…)->util = …;</tt>.</p>\r
+</dd>\r
+<dt>\r
+<tt>path_list_lookup</tt>\r
+</dt>\r
+<dd>\r
+<p>\r
+ Look up a given string in the path_list, returning the containing\r
+ path_list_item. If the string is not found, NULL is returned.\r
+</p>\r
+</dd>\r
+</dl>\r
+</li>\r
+<li>\r
+<p>\r
+Functions for unsorted lists only\r
+</p>\r
+<dl>\r
+<dt>\r
+<tt>path_list_append</tt>\r
+</dt>\r
+<dd>\r
+<p>\r
+ Append a new string to the end of the path_list.\r
+</p>\r
+</dd>\r
+<dt>\r
+<tt>sort_path_list</tt>\r
+</dt>\r
+<dd>\r
+<p>\r
+ Make an unsorted list sorted.\r
+</p>\r
+</dd>\r
+<dt>\r
+<tt>unsorted_path_list_has_path</tt>\r
+</dt>\r
+<dd>\r
+<p>\r
+ It's like <tt>path_list_has_path()</tt> but for unsorted lists.\r
+</p>\r
+<p>This function needs to look through all items, as opposed to its\r
+counterpart for sorted lists, which performs a binary search.</p>\r
+</dd>\r
+</dl>\r
</li>\r
</ul>\r
-<p>(Dscho)</p>\r
</div>\r
+<h2>Data structures</h2>\r
+<div class="sectionbody">\r
+<ul>\r
+<li>\r
+<p>\r
+<tt>struct path_list_item</tt>\r
+</p>\r
+</li>\r
+</ul>\r
+<p>Represents an item of the list. The <tt>path</tt> member is a pointer to the\r
+string, and you may use the <tt>util</tt> member for any purpose, if you want.</p>\r
+<ul>\r
+<li>\r
+<p>\r
+<tt>struct path_list</tt>\r
+</p>\r
+</li>\r
+</ul>\r
+<p>Represents the list itself.</p>\r
+<ol>\r
+<li>\r
+<p>\r
+The array of items are available via the <tt>items</tt> member.\r
+</p>\r
+</li>\r
+<li>\r
+<p>\r
+The <tt>nr</tt> member contains the number of items stored in the list.\r
+</p>\r
+</li>\r
+<li>\r
+<p>\r
+The <tt>alloc</tt> member is used to avoid reallocating at every insertion.\r
+ You should not tamper with it.\r
+</p>\r
+</li>\r
+<li>\r
+<p>\r
+Setting the <tt>strdup_paths</tt> member to 1 will strdup() the strings\r
+ before adding them, see above.\r
+</p>\r
+</li>\r
+</ol>\r
</div>\r
<div id="footer">\r
<div id="footer-text">\r
-Last updated 08-Jun-2008 01:34:45 UTC\r
+Last updated 18-Jun-2008 03:17:08 UTC\r
</div>\r
</div>\r
</body>\r
path-list API
=============
-Talk about <path-list.h>, things like
+The path_list API offers a data structure and functions to handle sorted
+and unsorted string lists.
-* it is not just paths but strings in general;
-* the calling sequence.
+The name is a bit misleading, a path_list may store not only paths but
+strings in general.
-(Dscho)
+The caller:
+
+. Allocates and clears a `struct path_list` variable.
+
+. Initializes the members. You might want to set the flag `strdup_paths`
+ if the strings should be strdup()ed. For example, this is necessary
+ when you add something like git_path("..."), since that function returns
+ a static buffer that will change with the next call to git_path().
++
+If you need something advanced, you can manually malloc() the `items`
+member (you need this if you add things later) and you should set the
+`nr` and `alloc` members in that case, too.
+
+. Adds new items to the list, using `path_list_append` or `path_list_insert`.
+
+. Can check if a string is in the list using `path_list_has_path` or
+ `unsorted_path_list_has_path` and get it from the list using
+ `path_list_lookup` for sorted lists.
+
+. Can sort an unsorted list using `sort_path_list`.
+
+. Finally it should free the list using `path_list_clear`.
+
+Example:
+
+----
+struct path_list list;
+int i;
+
+memset(&list, 0, sizeof(struct path_list));
+path_list_append("foo", &list);
+path_list_append("bar", &list);
+for (i = 0; i < list.nr; i++)
+ printf("%s\n", list.items[i].path)
+----
+
+NOTE: It is more efficient to build an unsorted list and sort it
+afterwards, instead of building a sorted list (`O(n log n)` instead of
+`O(n^2)`).
++
+However, if you use the list to check if a certain string was added
+already, you should not do that (using unsorted_path_list_has_path()),
+because the complexity would be quadratic again (but with a worse factor).
+
+Functions
+---------
+
+* General ones (works with sorted and unsorted lists as well)
+
+`print_path_list`::
+
+ Dump a path_list to stdout, useful mainly for debugging purposes. It
+ can take an optional header argument and it writes out the
+ string-pointer pairs of the path_list, each one in its own line.
+
+`path_list_clear`::
+
+ Free a path_list. The `path` pointer of the items will be freed in case
+ the `strdup_paths` member of the path_list is set. The second parameter
+ controls if the `util` pointer of the items should be freed or not.
+
+* Functions for sorted lists only
+
+`path_list_has_path`::
+
+ Determine if the path_list has a given string or not.
+
+`path_list_insert`::
+
+ Insert a new element to the path_list. The returned pointer can be handy
+ if you want to write something to the `util` pointer of the
+ path_list_item containing the just added string.
++
+Since this function uses xrealloc() (which die()s if it fails) if the
+list needs to grow, it is safe not to check the pointer. I.e. you may
+write `path_list_insert(...)->util = ...;`.
+
+`path_list_lookup`::
+
+ Look up a given string in the path_list, returning the containing
+ path_list_item. If the string is not found, NULL is returned.
+
+* Functions for unsorted lists only
+
+`path_list_append`::
+
+ Append a new string to the end of the path_list.
+
+`sort_path_list`::
+
+ Make an unsorted list sorted.
+
+`unsorted_path_list_has_path`::
+
+ It's like `path_list_has_path()` but for unsorted lists.
++
+This function needs to look through all items, as opposed to its
+counterpart for sorted lists, which performs a binary search.
+
+Data structures
+---------------
+
+* `struct path_list_item`
+
+Represents an item of the list. The `path` member is a pointer to the
+string, and you may use the `util` member for any purpose, if you want.
+
+* `struct path_list`
+
+Represents the list itself.
+
+. The array of items are available via the `items` member.
+. The `nr` member contains the number of items stored in the list.
+. The `alloc` member is used to avoid reallocating at every insertion.
+ You should not tamper with it.
+. Setting the `strdup_paths` member to 1 will strdup() the strings
+ before adding them, see above.
projects / git.git / commitdiff