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diff --git a/ctdb/lib/talloc/talloc.3.html b/ctdb/lib/talloc/talloc.3.html deleted file mode 100644 index 2459476435..0000000000 --- a/ctdb/lib/talloc/talloc.3.html +++ /dev/null @@ -1,433 +0,0 @@ -<html><head><meta http-equiv="Content-Type" content="text/html; charset=ISO-8859-1"><title>talloc</title><meta name="generator" content="DocBook XSL Stylesheets V1.71.0"></head><body bgcolor="white" text="black" link="#0000FF" vlink="#840084" alink="#0000FF"><div class="refentry" lang="en"><a name="id2478730"></a><div class="titlepage"></div><div class="refnamediv"><h2>Name</h2><p>talloc — hierarchical reference counted memory pool system with destructors</p></div><div class="refsynopsisdiv"><h2>Synopsis</h2><pre class="synopsis">#include <talloc/talloc.h></pre></div><div class="refsect1" lang="en"><a name="id2517362"></a><h2>DESCRIPTION</h2><p> - If you are used to talloc from Samba3 then please read this - carefully, as talloc has changed a lot. - </p><p> - The new talloc is a hierarchical, reference counted memory pool - system with destructors. Quite a mouthful really, but not too bad - once you get used to it. - </p><p> - Perhaps the biggest change from Samba3 is that there is no - distinction between a "talloc context" and a "talloc pointer". Any - pointer returned from talloc() is itself a valid talloc context. - This means you can do this: - </p><pre class="programlisting"> - struct foo *X = talloc(mem_ctx, struct foo); - X->name = talloc_strdup(X, "foo"); - </pre><p> - and the pointer <code class="literal">X->name</code> - would be a "child" of the talloc context <code class="literal">X</code> which is itself a child of - <code class="literal">mem_ctx</code>. So if you do - <code class="literal">talloc_free(mem_ctx)</code> then - it is all destroyed, whereas if you do <code class="literal">talloc_free(X)</code> then just <code class="literal">X</code> and <code class="literal">X->name</code> are destroyed, and if - you do <code class="literal">talloc_free(X->name)</code> then just - the name element of <code class="literal">X</code> is - destroyed. - </p><p> - If you think about this, then what this effectively gives you is an - n-ary tree, where you can free any part of the tree with - talloc_free(). - </p><p> - If you find this confusing, then I suggest you run the <code class="literal">testsuite</code> program to watch talloc - in action. You may also like to add your own tests to <code class="literal">testsuite.c</code> to clarify how some - particular situation is handled. - </p></div><div class="refsect1" lang="en"><a name="id2478829"></a><h2>TALLOC API</h2><p> - The following is a complete guide to the talloc API. Read it all at - least twice. - </p><div class="refsect2" lang="en"><a name="id2478838"></a><h3>(type *)talloc(const void *ctx, type);</h3><p> - The talloc() macro is the core of the talloc library. It takes a - memory <span class="italic">ctx</span> and a <span class="italic">type</span>, and returns a pointer to a new - area of memory of the given <span class="italic">type</span>. - </p><p> - The returned pointer is itself a talloc context, so you can use - it as the <span class="italic">ctx</span> argument to more - calls to talloc() if you wish. - </p><p> - The returned pointer is a "child" of the supplied context. This - means that if you talloc_free() the <span class="italic">ctx</span> then the new child disappears as - well. Alternatively you can free just the child. - </p><p> - The <span class="italic">ctx</span> argument to talloc() - can be NULL, in which case a new top level context is created. - </p></div><div class="refsect2" lang="en"><a name="id2478902"></a><h3>void *talloc_size(const void *ctx, size_t size);</h3><p> - The function talloc_size() should be used when you don't have a - convenient type to pass to talloc(). Unlike talloc(), it is not - type safe (as it returns a void *), so you are on your own for - type checking. - </p></div><div class="refsect2" lang="en"><a name="id2478915"></a><h3>(typeof(ptr)) talloc_ptrtype(const void *ctx, ptr);</h3><p> - The talloc_ptrtype() macro should be used when you have a pointer and - want to allocate memory to point at with this pointer. When compiling - with gcc >= 3 it is typesafe. Note this is a wrapper of talloc_size() - and talloc_get_name() will return the current location in the source file. - and not the type. - </p></div><div class="refsect2" lang="en"><a name="id2478930"></a><h3>int talloc_free(void *ptr);</h3><p> - The talloc_free() function frees a piece of talloc memory, and - all its children. You can call talloc_free() on any pointer - returned by talloc(). - </p><p> - The return value of talloc_free() indicates success or failure, - with 0 returned for success and -1 for failure. The only - possible failure condition is if <span class="italic">ptr</span> had a destructor attached to it and - the destructor returned -1. See <a href="#talloc_set_destructor" title="void talloc_set_destructor(const void *ptr, int (*destructor)(void *));">“<span class="quote">talloc_set_destructor()</span>”</a> - for details on destructors. - </p><p> - If this pointer has an additional parent when talloc_free() is - called then the memory is not actually released, but instead the - most recently established parent is destroyed. See <a href="#talloc_reference" title="void *talloc_reference(const void *ctx, const void *ptr);">“<span class="quote">talloc_reference()</span>”</a> - for details on establishing additional parents. - </p><p> - For more control on which parent is removed, see <a href="#talloc_unlink" title="int talloc_unlink(const void *ctx, const void *ptr);">“<span class="quote">talloc_unlink()</span>”</a>. - </p><p> - talloc_free() operates recursively on its children. - </p></div><div class="refsect2" lang="en"><a name="talloc_reference"></a><h3>void *talloc_reference(const void *ctx, const void *ptr);</h3><p> - The talloc_reference() function makes <span class="italic">ctx</span> an additional parent of <span class="italic">ptr</span>. - </p><p> - The return value of talloc_reference() is always the original - pointer <span class="italic">ptr</span>, unless talloc ran - out of memory in creating the reference in which case it will - return NULL (each additional reference consumes around 48 bytes - of memory on intel x86 platforms). - </p><p> - If <span class="italic">ptr</span> is NULL, then the - function is a no-op, and simply returns NULL. - </p><p> - After creating a reference you can free it in one of the - following ways: - </p><p> - </p><div class="itemizedlist"><ul type="disc"><li><p> - you can talloc_free() any parent of the original pointer. - That will reduce the number of parents of this pointer by 1, - and will cause this pointer to be freed if it runs out of - parents. - </p></li><li><p> - you can talloc_free() the pointer itself. That will destroy - the most recently established parent to the pointer and leave - the pointer as a child of its current parent. - </p></li></ul></div><p> - </p><p> - For more control on which parent to remove, see <a href="#talloc_unlink" title="int talloc_unlink(const void *ctx, const void *ptr);">“<span class="quote">talloc_unlink()</span>”</a>. - </p></div><div class="refsect2" lang="en"><a name="talloc_unlink"></a><h3>int talloc_unlink(const void *ctx, const void *ptr);</h3><p> - The talloc_unlink() function removes a specific parent from - <span class="italic">ptr</span>. The <span class="italic">ctx</span> passed must either be a context used - in talloc_reference() with this pointer, or must be a direct - parent of ptr. - </p><p> - Note that if the parent has already been removed using - talloc_free() then this function will fail and will return -1. - Likewise, if <span class="italic">ptr</span> is NULL, then - the function will make no modifications and return -1. - </p><p> - Usually you can just use talloc_free() instead of - talloc_unlink(), but sometimes it is useful to have the - additional control on which parent is removed. - </p></div><div class="refsect2" lang="en"><a name="talloc_set_destructor"></a><h3>void talloc_set_destructor(const void *ptr, int (*destructor)(void *));</h3><p> - The function talloc_set_destructor() sets the <span class="italic">destructor</span> for the pointer <span class="italic">ptr</span>. A <span class="italic">destructor</span> is a function that is called - when the memory used by a pointer is about to be released. The - destructor receives <span class="italic">ptr</span> as an - argument, and should return 0 for success and -1 for failure. - </p><p> - The <span class="italic">destructor</span> can do anything - it wants to, including freeing other pieces of memory. A common - use for destructors is to clean up operating system resources - (such as open file descriptors) contained in the structure the - destructor is placed on. - </p><p> - You can only place one destructor on a pointer. If you need more - than one destructor then you can create a zero-length child of - the pointer and place an additional destructor on that. - </p><p> - To remove a destructor call talloc_set_destructor() with NULL for - the destructor. - </p><p> - If your destructor attempts to talloc_free() the pointer that it - is the destructor for then talloc_free() will return -1 and the - free will be ignored. This would be a pointless operation - anyway, as the destructor is only called when the memory is just - about to go away. - </p></div><div class="refsect2" lang="en"><a name="id2479748"></a><h3>int talloc_increase_ref_count(const void *<span class="italic">ptr</span>);</h3><p> - The talloc_increase_ref_count(<span class="italic">ptr</span>) function is exactly equivalent to: - </p><pre class="programlisting">talloc_reference(NULL, ptr);</pre><p> - You can use either syntax, depending on which you think is - clearer in your code. - </p><p> - It returns 0 on success and -1 on failure. - </p></div><div class="refsect2" lang="en"><a name="id2479785"></a><h3>size_t talloc_reference_count(const void *<span class="italic">ptr</span>);</h3><p> - Return the number of references to the pointer. - </p></div><div class="refsect2" lang="en"><a name="talloc_set_name"></a><h3>void talloc_set_name(const void *ptr, const char *fmt, ...);</h3><p> - Each talloc pointer has a "name". The name is used principally - for debugging purposes, although it is also possible to set and - get the name on a pointer in as a way of "marking" pointers in - your code. - </p><p> - The main use for names on pointer is for "talloc reports". See - <a href="#talloc_report" title="void talloc_report(const void *ptr, FILE *f);">“<span class="quote">talloc_report_depth_cb()</span>”</a>, - <a href="#talloc_report" title="void talloc_report(const void *ptr, FILE *f);">“<span class="quote">talloc_report_depth_file()</span>”</a>, - <a href="#talloc_report" title="void talloc_report(const void *ptr, FILE *f);">“<span class="quote">talloc_report()</span>”</a> - <a href="#talloc_report" title="void talloc_report(const void *ptr, FILE *f);">“<span class="quote">talloc_report()</span>”</a> - and <a href="#talloc_report_full" title="void talloc_report_full(const void *ptr, FILE *f);">“<span class="quote">talloc_report_full()</span>”</a> - for details. Also see <a href="#talloc_enable_leak_report" title="void talloc_enable_leak_report(void);">“<span class="quote">talloc_enable_leak_report()</span>”</a> - and <a href="#talloc_enable_leak_report_full" title="void talloc_enable_leak_report_full(void);">“<span class="quote">talloc_enable_leak_report_full()</span>”</a>. - </p><p> - The talloc_set_name() function allocates memory as a child of the - pointer. It is logically equivalent to: - </p><pre class="programlisting">talloc_set_name_const(ptr, talloc_asprintf(ptr, fmt, ...));</pre><p> - Note that multiple calls to talloc_set_name() will allocate more - memory without releasing the name. All of the memory is released - when the ptr is freed using talloc_free(). - </p></div><div class="refsect2" lang="en"><a name="id2479904"></a><h3>void talloc_set_name_const(const void *<span class="italic">ptr</span>, const char *<span class="italic">name</span>);</h3><p> - The function talloc_set_name_const() is just like - talloc_set_name(), but it takes a string constant, and is much - faster. It is extensively used by the "auto naming" macros, such - as talloc_p(). - </p><p> - This function does not allocate any memory. It just copies the - supplied pointer into the internal representation of the talloc - ptr. This means you must not pass a <span class="italic">name</span> pointer to memory that will - disappear before <span class="italic">ptr</span> is freed - with talloc_free(). - </p></div><div class="refsect2" lang="en"><a name="id2479948"></a><h3>void *talloc_named(const void *<span class="italic">ctx</span>, size_t <span class="italic">size</span>, const char *<span class="italic">fmt</span>, ...);</h3><p> - The talloc_named() function creates a named talloc pointer. It - is equivalent to: - </p><pre class="programlisting">ptr = talloc_size(ctx, size); -talloc_set_name(ptr, fmt, ....);</pre></div><div class="refsect2" lang="en"><a name="id2479983"></a><h3>void *talloc_named_const(const void *<span class="italic">ctx</span>, size_t <span class="italic">size</span>, const char *<span class="italic">name</span>);</h3><p> - This is equivalent to: - </p><pre class="programlisting">ptr = talloc_size(ctx, size); -talloc_set_name_const(ptr, name);</pre></div><div class="refsect2" lang="en"><a name="id2480018"></a><h3>const char *talloc_get_name(const void *<span class="italic">ptr</span>);</h3><p> - This returns the current name for the given talloc pointer, - <span class="italic">ptr</span>. See <a href="#talloc_set_name" title="void talloc_set_name(const void *ptr, const char *fmt, ...);">“<span class="quote">talloc_set_name()</span>”</a> - for details. - </p></div><div class="refsect2" lang="en"><a name="id2480049"></a><h3>void *talloc_init(const char *<span class="italic">fmt</span>, ...);</h3><p> - This function creates a zero length named talloc context as a top - level context. It is equivalent to: - </p><pre class="programlisting">talloc_named(NULL, 0, fmt, ...);</pre></div><div class="refsect2" lang="en"><a name="id2480072"></a><h3>void *talloc_new(void *<span class="italic">ctx</span>);</h3><p> - This is a utility macro that creates a new memory context hanging - off an exiting context, automatically naming it "talloc_new: - __location__" where __location__ is the source line it is called - from. It is particularly useful for creating a new temporary - working context. - </p></div><div class="refsect2" lang="en"><a name="id2526763"></a><h3>(<span class="italic">type</span> *)talloc_realloc(const void *<span class="italic">ctx</span>, void *<span class="italic">ptr</span>, <span class="italic">type</span>, <span class="italic">count</span>);</h3><p> - The talloc_realloc() macro changes the size of a talloc pointer. - It has the following equivalences: - </p><pre class="programlisting">talloc_realloc(ctx, NULL, type, 1) ==> talloc(ctx, type); -talloc_realloc(ctx, ptr, type, 0) ==> talloc_free(ptr);</pre><p> - The <span class="italic">ctx</span> argument is only used - if <span class="italic">ptr</span> is not NULL, otherwise - it is ignored. - </p><p> - talloc_realloc() returns the new pointer, or NULL on failure. - The call will fail either due to a lack of memory, or because the - pointer has more than one parent (see <a href="#talloc_reference" title="void *talloc_reference(const void *ctx, const void *ptr);">“<span class="quote">talloc_reference()</span>”</a>). - </p></div><div class="refsect2" lang="en"><a name="id2526841"></a><h3>void *talloc_realloc_size(const void *ctx, void *ptr, size_t size);</h3><p> - the talloc_realloc_size() function is useful when the type is not - known so the type-safe talloc_realloc() cannot be used. - </p></div><div class="refsect2" lang="en"><a name="id2526853"></a><h3>TYPE *talloc_steal(const void *<span class="italic">new_ctx</span>, const TYPE *<span class="italic">ptr</span>);</h3><p> - The talloc_steal() function changes the parent context of a - talloc pointer. It is typically used when the context that the - pointer is currently a child of is going to be freed and you wish - to keep the memory for a longer time. - </p><p> - The talloc_steal() function returns the pointer that you pass it. - It does not have any failure modes. - </p><p> - NOTE: It is possible to produce loops in the parent/child - relationship if you are not careful with talloc_steal(). No - guarantees are provided as to your sanity or the safety of your - data if you do this. - </p></div><div class="refsect2" lang="en"><a name="id2526890"></a><h3>TYPE *talloc_move(const void *<span class="italic">new_ctx</span>, TYPE **<span class="italic">ptr</span>);</h3><p> - The talloc_move() function is a wrapper around - talloc_steal() which zeros the source pointer after the - move. This avoids a potential source of bugs where a - programmer leaves a pointer in two structures, and uses the - pointer from the old structure after it has been moved to a - new one. - </p></div><div class="refsect2" lang="en"><a name="id2526916"></a><h3>size_t talloc_total_size(const void *<span class="italic">ptr</span>);</h3><p> - The talloc_total_size() function returns the total size in bytes - used by this pointer and all child pointers. Mostly useful for - debugging. - </p><p> - Passing NULL is allowed, but it will only give a meaningful - result if talloc_enable_leak_report() or - talloc_enable_leak_report_full() has been called. - </p></div><div class="refsect2" lang="en"><a name="id2526940"></a><h3>size_t talloc_total_blocks(const void *<span class="italic">ptr</span>);</h3><p> - The talloc_total_blocks() function returns the total memory block - count used by this pointer and all child pointers. Mostly useful - for debugging. - </p><p> - Passing NULL is allowed, but it will only give a meaningful - result if talloc_enable_leak_report() or - talloc_enable_leak_report_full() has been called. - </p></div><div class="refsect2" lang="en"><a name="talloc_report"></a><h3>void talloc_report(const void *ptr, FILE *f);</h3><p> - The talloc_report() function prints a summary report of all - memory used by <span class="italic">ptr</span>. One line - of report is printed for each immediate child of ptr, showing the - total memory and number of blocks used by that child. - </p><p> - You can pass NULL for the pointer, in which case a report is - printed for the top level memory context, but only if - talloc_enable_leak_report() or talloc_enable_leak_report_full() - has been called. - </p></div><div class="refsect2" lang="en"><a name="talloc_report_full"></a><h3>void talloc_report_full(const void *<span class="italic">ptr</span>, FILE *<span class="italic">f</span>);</h3><p> - This provides a more detailed report than talloc_report(). It - will recursively print the entire tree of memory referenced by - the pointer. References in the tree are shown by giving the name - of the pointer that is referenced. - </p><p> - You can pass NULL for the pointer, in which case a report is - printed for the top level memory context, but only if - talloc_enable_leak_report() or talloc_enable_leak_report_full() - has been called. - </p></div><div class="refsect2" lang="en"><a name="talloc_report_depth_cb"></a><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0" style="padding-bottom: 1em"><tr><td><code class="funcdef">void <b class="fsfunc">talloc_report_depth_cb</b>(</code></td><td><var class="pdparam">const void *ptr</var>, </td><td> </td></tr><tr><td> </td><td><var class="pdparam">int depth</var>, </td><td> </td></tr><tr><td> </td><td><var class="pdparam">int max_depth</var>, </td><td> </td></tr><tr><td> </td><td><var class="pdparam">void (*callback)(const void *ptr, int depth, int max_depth, int is_ref, void *priv)</var>, </td><td> </td></tr><tr><td> </td><td><var class="pdparam">void *priv</var><code>)</code>;</td><td> </td></tr></table><table border="0" summary="Function argument synopsis" cellspacing="0" cellpadding="0"><tr><td><code></code> </td><td><code><var class="pdparam">const void *ptr</var>;</code></td></tr><tr><td><code></code> </td><td><code><var class="pdparam">int depth</var>;</code></td></tr><tr><td><code></code> </td><td><code><var class="pdparam">int max_depth</var>;</code></td></tr><tr><td><code></code> </td><td><code><var class="pdparam">void (*callback)(const void *ptr, int depth, int max_depth, int is_ref, void *priv)</var>;</code></td></tr><tr><td><code></code> </td><td><code><var class="pdparam">void *priv</var>;</code></td></tr></table></div><p> - This provides a more flexible reports than talloc_report(). It - will recursively call the callback for the entire tree of memory - referenced by the pointer. References in the tree are passed with - <span class="italic">is_ref = 1</span> and the pointer that is referenced. - </p><p> - You can pass NULL for the pointer, in which case a report is - printed for the top level memory context, but only if - talloc_enable_leak_report() or talloc_enable_leak_report_full() - has been called. - </p><p> - The recursion is stopped when depth >= max_depth. - max_depth = -1 means only stop at leaf nodes. - </p></div><div class="refsect2" lang="en"><a name="talloc_report_depth_file"></a><div class="funcsynopsis"><table border="0" summary="Function synopsis" cellspacing="0" cellpadding="0" style="padding-bottom: 1em"><tr><td><code class="funcdef">void <b class="fsfunc">talloc_report_depth_file</b>(</code></td><td><var class="pdparam">const void *ptr</var>, </td><td> </td></tr><tr><td> </td><td><var class="pdparam">int depth</var>, </td><td> </td></tr><tr><td> </td><td><var class="pdparam">int max_depth</var>, </td><td> </td></tr><tr><td> </td><td><var class="pdparam">FILE *f</var><code>)</code>;</td><td> </td></tr></table><table border="0" summary="Function argument synopsis" cellspacing="0" cellpadding="0"><tr><td><code></code> </td><td><code><var class="pdparam">const void *ptr</var>;</code></td></tr><tr><td><code></code> </td><td><code><var class="pdparam">int depth</var>;</code></td></tr><tr><td><code></code> </td><td><code><var class="pdparam">int max_depth</var>;</code></td></tr><tr><td><code></code> </td><td><code><var class="pdparam">FILE *f</var>;</code></td></tr></table></div><p> - This provides a more flexible reports than talloc_report(). It - will let you specify the depth and max_depth. - </p></div><div class="refsect2" lang="en"><a name="talloc_enable_leak_report"></a><h3>void talloc_enable_leak_report(void);</h3><p> - This enables calling of talloc_report(NULL, stderr) when the - program exits. In Samba4 this is enabled by using the - --leak-report command line option. - </p><p> - For it to be useful, this function must be called before any - other talloc function as it establishes a "null context" that - acts as the top of the tree. If you don't call this function - first then passing NULL to talloc_report() or - talloc_report_full() won't give you the full tree printout. - </p><p> - Here is a typical talloc report: - </p><pre class="screen">talloc report on 'null_context' (total 267 bytes in 15 blocks) -libcli/auth/spnego_parse.c:55 contains 31 bytes in 2 blocks -libcli/auth/spnego_parse.c:55 contains 31 bytes in 2 blocks -iconv(UTF8,CP850) contains 42 bytes in 2 blocks -libcli/auth/spnego_parse.c:55 contains 31 bytes in 2 blocks -iconv(CP850,UTF8) contains 42 bytes in 2 blocks -iconv(UTF8,UTF-16LE) contains 45 bytes in 2 blocks -iconv(UTF-16LE,UTF8) contains 45 bytes in 2 blocks - </pre></div><div class="refsect2" lang="en"><a name="talloc_enable_leak_report_full"></a><h3>void talloc_enable_leak_report_full(void);</h3><p> - This enables calling of talloc_report_full(NULL, stderr) when the - program exits. In Samba4 this is enabled by using the - --leak-report-full command line option. - </p><p> - For it to be useful, this function must be called before any - other talloc function as it establishes a "null context" that - acts as the top of the tree. If you don't call this function - first then passing NULL to talloc_report() or - talloc_report_full() won't give you the full tree printout. - </p><p> - Here is a typical full report: - </p><pre class="screen">full talloc report on 'root' (total 18 bytes in 8 blocks) -p1 contains 18 bytes in 7 blocks (ref 0) - r1 contains 13 bytes in 2 blocks (ref 0) - reference to: p2 - p2 contains 1 bytes in 1 blocks (ref 1) - x3 contains 1 bytes in 1 blocks (ref 0) - x2 contains 1 bytes in 1 blocks (ref 0) - x1 contains 1 bytes in 1 blocks (ref 0) - </pre></div><div class="refsect2" lang="en"><a name="id2527248"></a><h3>(<span class="italic">type</span> *)talloc_zero(const void *<span class="italic">ctx</span>, <span class="italic">type</span>);</h3><p> - The talloc_zero() macro is equivalent to: - </p><pre class="programlisting">ptr = talloc(ctx, type); -if (ptr) memset(ptr, 0, sizeof(type));</pre></div><div class="refsect2" lang="en"><a name="id2527281"></a><h3>void *talloc_zero_size(const void *<span class="italic">ctx</span>, size_t <span class="italic">size</span>)</h3><p> - The talloc_zero_size() function is useful when you don't have a - known type. - </p></div><div class="refsect2" lang="en"><a name="id2527304"></a><h3>void *talloc_memdup(const void *<span class="italic">ctx</span>, const void *<span class="italic">p</span>, size_t size);</h3><p> - The talloc_memdup() function is equivalent to: - </p><pre class="programlisting">ptr = talloc_size(ctx, size); -if (ptr) memcpy(ptr, p, size);</pre></div><div class="refsect2" lang="en"><a name="id2527332"></a><h3>char *talloc_strdup(const void *<span class="italic">ctx</span>, const char *<span class="italic">p</span>);</h3><p> - The talloc_strdup() function is equivalent to: - </p><pre class="programlisting">ptr = talloc_size(ctx, strlen(p)+1); -if (ptr) memcpy(ptr, p, strlen(p)+1);</pre><p> - This function sets the name of the new pointer to the passed - string. This is equivalent to: - </p><pre class="programlisting">talloc_set_name_const(ptr, ptr)</pre></div><div class="refsect2" lang="en"><a name="id2527372"></a><h3>char *talloc_strndup(const void *<span class="italic">t</span>, const char *<span class="italic">p</span>, size_t <span class="italic">n</span>);</h3><p> - The talloc_strndup() function is the talloc equivalent of the C - library function strndup(3). - </p><p> - This function sets the name of the new pointer to the passed - string. This is equivalent to: - </p><pre class="programlisting">talloc_set_name_const(ptr, ptr)</pre></div><div class="refsect2" lang="en"><a name="id2527412"></a><h3>char *talloc_vasprintf(const void *<span class="italic">t</span>, const char *<span class="italic">fmt</span>, va_list <span class="italic">ap</span>);</h3><p> - The talloc_vasprintf() function is the talloc equivalent of the C - library function vasprintf(3). - </p></div><div class="refsect2" lang="en"><a name="id2527441"></a><h3>char *talloc_asprintf(const void *<span class="italic">t</span>, const char *<span class="italic">fmt</span>, ...);</h3><p> - The talloc_asprintf() function is the talloc equivalent of the C - library function asprintf(3). - </p><p> - This function sets the name of the new pointer to the passed - string. This is equivalent to: - </p><pre class="programlisting">talloc_set_name_const(ptr, ptr)</pre></div><div class="refsect2" lang="en"><a name="id2527475"></a><h3>char *talloc_asprintf_append(char *s, const char *fmt, ...);</h3><p> - The talloc_asprintf_append() function appends the given formatted - string to the given string. - </p></div><div class="refsect2" lang="en"><a name="id2527486"></a><h3>(type *)talloc_array(const void *ctx, type, uint_t count);</h3><p> - The talloc_array() macro is equivalent to: - </p><pre class="programlisting">(type *)talloc_size(ctx, sizeof(type) * count);</pre><p> - except that it provides integer overflow protection for the - multiply, returning NULL if the multiply overflows. - </p></div><div class="refsect2" lang="en"><a name="id2527509"></a><h3>void *talloc_array_size(const void *ctx, size_t size, uint_t count);</h3><p> - The talloc_array_size() function is useful when the type is not - known. It operates in the same way as talloc_array(), but takes a - size instead of a type. - </p></div><div class="refsect2" lang="en"><a name="id2527522"></a><h3>(typeof(ptr)) talloc_array_ptrtype(const void *ctx, ptr, uint_t count);</h3><p> - The talloc_ptrtype() macro should be used when you have a pointer to an array - and want to allocate memory of an array to point at with this pointer. When compiling - with gcc >= 3 it is typesafe. Note this is a wrapper of talloc_array_size() - and talloc_get_name() will return the current location in the source file. - and not the type. - </p></div><div class="refsect2" lang="en"><a name="id2527538"></a><h3>void *talloc_realloc_fn(const void *ctx, void *ptr, size_t size)</h3><p> - This is a non-macro version of talloc_realloc(), which is useful - as libraries sometimes want a realloc function pointer. A - realloc(3) implementation encapsulates the functionality of - malloc(3), free(3) and realloc(3) in one call, which is why it is - useful to be able to pass around a single function pointer. - </p></div><div class="refsect2" lang="en"><a name="id2527554"></a><h3>void *talloc_autofree_context(void);</h3><p> - This is a handy utility function that returns a talloc context - which will be automatically freed on program exit. This can be - used to reduce the noise in memory leak reports. - </p></div><div class="refsect2" lang="en"><a name="id2527566"></a><h3>void *talloc_check_name(const void *ptr, const char *name);</h3><p> - This function checks if a pointer has the specified <span class="italic">name</span>. If it does then the pointer is - returned. It it doesn't then NULL is returned. - </p></div><div class="refsect2" lang="en"><a name="id2527584"></a><h3>(type *)talloc_get_type(const void *ptr, type);</h3><p> - This macro allows you to do type checking on talloc pointers. It - is particularly useful for void* private pointers. It is - equivalent to this: - </p><pre class="programlisting">(type *)talloc_check_name(ptr, #type)</pre></div><div class="refsect2" lang="en"><a name="id2527603"></a><h3>talloc_set_type(const void *ptr, type);</h3><p> - This macro allows you to force the name of a pointer to be a - particular <span class="emphasis"><em>type</em></span>. This can be - used in conjunction with talloc_get_type() to do type checking on - void* pointers. - </p><p> - It is equivalent to this: - </p><pre class="programlisting">talloc_set_name_const(ptr, #type)</pre></div></div><div class="refsect1" lang="en"><a name="id2527631"></a><h2>PERFORMANCE</h2><p> - All the additional features of talloc(3) over malloc(3) do come at a - price. We have a simple performance test in Samba4 that measures - talloc() versus malloc() performance, and it seems that talloc() is - about 10% slower than malloc() on my x86 Debian Linux box. For - Samba, the great reduction in code complexity that we get by using - talloc makes this worthwhile, especially as the total overhead of - talloc/malloc in Samba is already quite small. - </p></div><div class="refsect1" lang="en"><a name="id2527648"></a><h2>SEE ALSO</h2><p> - malloc(3), strndup(3), vasprintf(3), asprintf(3), - <a href="http://talloc.samba.org/" target="_top">http://talloc.samba.org/</a> - </p></div><div class="refsect1" lang="en"><a name="id2527662"></a><h2>COPYRIGHT/LICENSE</h2><p> - Copyright (C) Andrew Tridgell 2004 - </p><p> - This program is free software; you can redistribute it and/or modify - it under the terms of the GNU General Public License as published by - the Free Software Foundation; either version 3 of the License, or (at - your option) any later version. - </p><p> - This program is distributed in the hope that it will be useful, but - WITHOUT ANY WARRANTY; without even the implied warranty of - MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU - General Public License for more details. - </p><p> - You should have received a copy of the GNU General Public License - along with this program; if not, write to the Free Software - Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA. - </p></div></div></body></html> |