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diff --git a/doc/libdatastruct/genqdyn.html b/doc/libdatastruct/genqdyn.html new file mode 100644 index 0000000..4f1c8f1 --- /dev/null +++ b/doc/libdatastruct/genqdyn.html @@ -0,0 +1,127 @@ +<html> + <head> + <meta name="viewport" content="width=device-width, initial-scale=1.0" /> + <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> + <meta http-equiv="Content-Language" content="en" /> + <title>skalibs: the genqdyn library interface</title> + <meta name="Description" content="skalibs: the genqdyn library interface" /> + <meta name="Keywords" content="skalibs c unix genqdyn library queue libdatastruct" /> + <!-- <link rel="stylesheet" type="text/css" href="//skarnet.org/default.css" /> --> + </head> +<body> + +<p> +<a href="index.html">libdatastruct</a><br /> +<a href="../libskarnet.html">libskarnet</a><br /> +<a href="../index.html">skalibs</a><br /> +<a href="//skarnet.org/software/">Software</a><br /> +<a href="//skarnet.org/">skarnet.org</a> +</p> + +<h1> The <tt>genqdyn</tt> library interface </h1> + +<p> + The following functions are declared in the <tt>skalibs/genqdyn.h</tt> header, +and implemented in the <tt>libskarnet.a</tt> or <tt>libskarnet.so</tt> library. +</p> + +<h2> General information </h2> + +<p> + <tt>genqdyn</tt> is a set of functions implementing simple queues on +generic objects. The <em>dyn</em> prefix means the queues are dynamically +allocated (and live in heap memory): it is possible to enqueue an arbitrary +number of objects, up to the available memory. +</p> + +<h2> Data structures </h2> + +<p> + A <tt>genqdyn</tt> structure holds the information necessary to implement +a queue. It can be declared anywhere (including in the stack). All genqdyn +functions take a pointer to this structure as an argument. +</p> + +<h2> Macros </h2> + +<p> +<code> genqdyn GENQDYN_INIT(type, num, den) </code> <br /> +Returns an anonymous genqdyn structure suitable for holding objects of +type <em>type</em>. The <em>num</em> and <em>den</em> arguments are integers, +used to tune the amount of memory needed / management overhead balance. +<em>num</em>/<em>den</em> must be a fractional value between 0 and 1. +The closer to 0, the longer genqdyn will wait before performing a +cleanup (and the more memory it can consume). At 0, genqdyn can only +recycle memory when the queue becomes totally empty. The closer to 1, +the more genqdyn optimizes its memory usage (and the more often it +performs maintenance on its queue). At 1, it performs maintenance +every time an object is popped. + Anything between 1/4 and 3/4 is a reasonable value for <em>num</em>/<em>den</em>. +</p> + +<p> +<code> size_t genqdyn_n (genqdyn *g) </code> <br /> +Returns the number of elements in the genqdyn <em>*g</em>, which must +have been initialized. +</p> + +<p> +<code> void *genqdyn_peek (genqdyn *g) </code> <br /> +Peeks at the next object in the queue, i.e. the object that has +been pushed the earliest and that hasn't been popped yet. +You can use the <tt>GENQDYN_PEEK(type, g)</tt> macro to get a +<tt>type *</tt> pointer instead of a <tt>void *</tt> one. +</p> + + + +<h2> Functions </h2> + +<p> +<code> void genqdyn_init (genqdyn *g, size_t esize, unsigned int den, unsigned int den) </code> <br /> +Initializes the genqdyn <em>*g</em> to hold objects of size <em>esize</em>. +<em>g</em> must be unused, or have been freed. The <em>num</em> and <em>den</em> +arguments tune <em>g</em>'s behaviour as described above in the GENQDYN_INIT +description. This function is similar to the GENQDYN_INIT macro, except that +it can be used dynamically and works on a pre-declared genqdyn, whereas the +macro can only be used as a static initializer. +</p> + +<p> +<code> void genqdyn_init (genqdyn *g, size_t esize, unsigned int den, unsigned int den) </code> <br /> +Initializes the genqdyn <em>*g</em> to hold objects of size <em>esize</em>. +<em>g</em> must be unused, or have been freed. The <em>num</em> and <em>den</em> +arguments tune <em>g</em>'s behaviour as described above in the GENQDYN_INIT +description. +</p> + +<p> +<code> void genqdyn_free (genqdyn *g) </code> <br /> +Frees the resources used by <em>*g</em>, which is then considered +uninitialized. +</p> + +<p> +<code> int genqdyn_push (genqdyn *g, void const *p) </code> <br /> + Pushes the object pointed to by <em>p</em> onto the queue. This object +must have the same size that has been given to the <tt>genqdyn_init()</tt> +invocation, or be of the same type that has been given to the +<tt>GENQDYN_INIT()</tt> invocation. The function returns 1 if it succeeds +and 0 (and sets errno) if it fails. +</p> + +<p> +<code> int genqdyn_unpush (genqdyn *g) </code> <br /> + Undoes the last push. Returns 1, except if the queue is empty, +in which case it returns 0 and sets errno to EINVAL. +</p> + +<p> +<code> int genqdyn_pop (genqdyn *g) </code> <br /> + Pops an object from the queue, and possibly performs maintenance +to reuse some memory. Returns 1, unless the queue is empty, in which +case it returns 0 and sets errno to EINVAL. +</p> + +</body> +</html> diff --git a/doc/libdatastruct/index.html b/doc/libdatastruct/index.html index 2ecf854..a0cf918 100644 --- a/doc/libdatastruct/index.html +++ b/doc/libdatastruct/index.html @@ -34,8 +34,14 @@ lists and AVL trees, in a memory-efficient and CPU-efficient way. <h2> Programming </h2> <p> -FIXME: to be completed. + <tt>skalibs/datastruct.h</tt> is a collection of several headers, each +one defining a specific data structure and providing functions to work on it. </p> +<ul> + <li> <a href="genqdyn.html"><tt>skalibs/genqdyn.h</tt></a>: dynamically allocated queues for generic objects </li> + <li> FIXME: To be completed </li> +</ul> + </body> </html> |