talloc_string(3)

🎀 talloc_string(3) 🎀

okay so this page comes from the Library Functions Manual, and it's literally the talloc_string page. Bestie, it's all about the talloc string functions — allocation and manipulation, the whole vibe. 💅

✨ NAME ✨

talloc_string — The talloc string functions.

• talloc string allocation and manipulation functions. 🫶

🌈 SYNOPSIS 🌈

Here's the map, bestie — topics and functions, no cap:

🎀 Topics 🎀

🧚 The talloc debugging support functions 🧚

To aid memory debugging, talloc contains routines to inspect the currently allocated memory hierarchy. That's the debug-support corner of the talloc universe. 🔥

💖 Functions 💖

The full function roster is giving organized main character energy — every signature stays exactly as it is:

• _PUBLIC_ char * talloc_strdup (const void *t, const char *p) — Duplicate a string into a talloc chunk. ✨
• _PUBLIC_ char * talloc_strdup_append (char *s, const char *a) — Append a string to given string. 💅
• _PUBLIC_ char * talloc_strdup_append_buffer (char *s, const char *a) — Append a string to a given buffer. 🫶
• _PUBLIC_ char * talloc_strndup (const void *t, const char *p, size_t n) — Duplicate a length-limited string into a talloc chunk. 🎀
• _PUBLIC_ char * talloc_strndup_append (char *s, const char *a, size_t n) — Append at most n characters of a string to given string. 🌸
• _PUBLIC_ char * talloc_strndup_append_buffer (char *s, const char *a, size_t n) — Append at most n characters of a string to given buffer. 🦋
• _PUBLIC_ char * talloc_vasprintf (const void *t, const char *fmt, va_list ap) — Format a string given a va_list. ⭐
• _PUBLIC_ char * talloc_vasprintf_append (char *s, const char *fmt, va_list ap) — Format a string given a va_list and append it to the given destination string. 💖
• _PUBLIC_ char * talloc_vasprintf_append_buffer (char *s, const char *fmt, va_list ap) — Format a string given a va_list and append it to the given destination buffer. 🌈
• _PUBLIC_ void talloc_asprintf_addbuf (char **ps, const char *fmt,...) — Build up a string buffer, handle allocation failure. Responsible icon behavior. 👑
• _PUBLIC_ char * talloc_asprintf (const void *t, const char *fmt,...) — Format a string. Periodt. 🔥
• _PUBLIC_ char * talloc_asprintf_append (char *s, const char *fmt,...) — Append a formatted string to another string. 💜
• _PUBLIC_ char * talloc_asprintf_append_buffer (char *s, const char *fmt,...) — Append a formatted string to another string. 🍓

💜 Detailed Description 💜

talloc string allocation and manipulation functions. That's the whole summary — talloc string allocation and manipulation functions, literally. 🦋

✨ talloc_asprintf() ✨

_PUBLIC_ char * talloc_asprintf (const void * t, const char * fmt,  ...)

Format a string, bestie — this is literally the talloc glow-up of the C library's asprintf(3). 💅

Okay so it also sets the name of the new pointer to the new string. Like, exactly equivalent to:

talloc_set_name_const(ptr, ptr)

Parameters

• t — the talloc context you're hanging the result off of 🎀
• fmt — the format string
• ... — the parameters used to fill fmt

Returns

The formatted string, or NULL on error. 😭

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✨ talloc_asprintf_addbuf() ✨

_PUBLIC_ void talloc_asprintf_addbuf (char ** ps, const char * fmt,  ...)

Build up a string buffer — and handle allocation failure while you're at it. Iconic behaviour tbh. ✨

Parameters

• ps — pointer to the talloc'ed string you wanna extend
• fmt — the format string
• ... — the parameters used to fill fmt

Here's the slay part: this does nothing if *ps is NULL, and it sets *ps to NULL if the intermediate reallocation fails. So it's genuinely useful when you're building up a string step by step — no intermediate NULL checks required. Periodt. 💅

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✨ talloc_asprintf_append() ✨

_PUBLIC_ char * talloc_asprintf_append (char * s, const char * fmt,  ...)

Appends a formatted string to another string, fr fr. Use this variant when the string in the current talloc buffer may have been truncated in length — that's the whole vibe check on this one. 🦋

It sets the name of the new pointer to the new string, equivalent to:

talloc_set_name_const(ptr, ptr)

And if s == NULL, a whole new context gets created. 👑

Parameters

• s — the string to append to
• fmt — the format string
• ... — the parameters used to fill fmt

Returns

The formatted string, or NULL on error.

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✨ talloc_asprintf_append_buffer() ✨

_PUBLIC_ char * talloc_asprintf_append_buffer (char * s, const char * fmt,
    ...)

Appends a formatted string to another string, but this is the more efficient version of talloc_asprintf_append(). It figures out the length of the destination string from the size of the talloc context instead of from the string itself. Efficiency ate, ngl. 🔥

⚠️ Use this very carefully — it produces a different result than talloc_asprintf_append() when there's a zero character in the middle of the destination string. Like, not a cute difference. Pay attention. 💀

Check it:

char *str_a = talloc_strdup(NULL, "hello world");
char *str_b = talloc_strdup(NULL, "hello world");
str_a[5] = str_b[5] = '\0'

char *app = talloc_asprintf_append(str_a, "%s", ", hello");
char *buf = talloc_strdup_append_buffer(str_b, "%s", ", hello");

printf("%s\n", app); // hello, hello (app = "hello, hello")
printf("%s\n", buf); // hello (buf = "hello\0world, hello")

See how they diverge?? buf keeps the whole buffer including the stuff after the \0. 🙈

If s == NULL then a new context is created.

Parameters

• s — the string to append to
• fmt — the format string
• ... — the parameters used to fill fmt

Returns

The formatted string, or NULL on error.

See also

• talloc_asprintf()
• talloc_asprintf_append()

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✨ talloc_strdup() ✨

_PUBLIC_ char * talloc_strdup (const void * t, const char * p)

Duplicates a string into a talloc chunk. It's equivalent to:

ptr = talloc_size(ctx, strlen(p)+1);
if (ptr) memcpy(ptr, p, strlen(p)+1);

It sets the name of the new pointer to the string you passed in, equivalent to:

talloc_set_name_const(ptr, ptr)

Parameters

• t — the talloc context to hang the result off of
• p — the string you wanna duplicate 🌸

Returns

The duplicated string, or NULL on error.

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✨ talloc_strdup_append() ✨

_PUBLIC_ char * talloc_strdup_append (char * s, const char * a)

Appends a string to a given string. The destination string gets reallocated to take strlen(s) + strlen(a) + 1 characters. Math, but make it cute. 🧮✨

It sets the name of the new pointer to the new string, equivalent to:

talloc_set_name_const(ptr, ptr)

If s == NULL then a new context is created.

Parameters

• s — the destination to append to
• a — the string you wanna append

Returns

The concatenated strings, or NULL on error.

See also

• talloc_strdup()
• talloc_strdup_append_buffer()

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✨ talloc_strdup_append_buffer() ✨

_PUBLIC_ char * talloc_strdup_append_buffer (char * s, const char * a)

Appends a string to a given buffer — the more efficient version of talloc_strdup_append(). It determines the length of the destination string by the size of the talloc context. 🦋

⚠️ Again: use this very carefully. It produces a different result than talloc_strdup_append() when there's a zero character in the middle of the destination string. Bestie I'm serious. 💀

char *str_a = talloc_strdup(NULL, "hello world");
char *str_b = talloc_strdup(NULL, "hello world");
str_a[5] = str_b[5] = '\0'

char *app = talloc_strdup_append(str_a, ", hello");
char *buf = talloc_strdup_append_buffer(str_b, ", hello");

printf("%s\n", app); // hello, hello (app = "hello, hello")
printf("%s\n", buf); // hello (buf = "hello\0world, hello")

If s == NULL then a new context is created.

Parameters

• s — the destination buffer to append to
• a — the string you wanna append

Returns

The concatenated strings, or NULL on error.

See also

• talloc_strdup()
• talloc_strdup_append()
• talloc_array_length()

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✨ talloc_strndup() ✨

_PUBLIC_ char * talloc_strndup (const void * t, const char * p, size_t n)

Duplicates a length-limited string into a talloc chunk. This is the talloc equivalent of the C library's strndup(3). 🎀

It sets the name of the new pointer to the string you passed in, equivalent to:

talloc_set_name_const(ptr, ptr)

Parameters

• t — the talloc context to hang the result off of
• p — the string you wanna duplicate
• n — the maximum string length to duplicate

Returns

The duplicated string, or NULL on error.

---

✨ talloc_strndup_append() ✨

_PUBLIC_ char * talloc_strndup_append (char * s, const char * a, size_t n)

Appends at most n characters of a string to a given string. The destination string gets reallocated to take strlen(s) + strnlen(a, n) + 1 characters. 🌸

It sets the name of the new pointer to the new string, equivalent to:

talloc_set_name_const(ptr, ptr)

If s == NULL then a new context is created.

Parameters

• s — the destination string to append to
• a — the source string you wanna append
• n — the number of characters you wanna append from the string

Returns

The concatenated strings, or NULL on error.

See also

• talloc_strndup()
• talloc_strndup_append_buffer()

---

✨ talloc_strndup_append_buffer() ✨

_PUBLIC_ char * talloc_strndup_append_buffer (char * s, const char * a,
    size_t n)

Appends at most n characters of a string to a given buffer — the more efficient version of talloc_strndup_append(). It determines the length of the destination string by the size of the talloc context. 🔥

⚠️ Careful, careful, careful: it produces a different result than talloc_strndup_append() when a zero character sits in the middle of the destination string. 💀

char *str_a = talloc_strdup(NULL, "hello world");
char *str_b = talloc_strdup(NULL, "hello world");
str_a[5] = str_b[5] = '\0'

char *app = talloc_strndup_append(str_a, ", hello", 7);
char *buf = talloc_strndup_append_buffer(str_b, ", hello", 7);

printf("%s\n", app); // hello, hello (app = "hello, hello")
printf("%s\n", buf); // hello (buf = "hello\0world, hello")

If s == NULL then a new context is created.

Parameters

• s — the destination buffer to append to
• a — the source string you wanna append
• n — the number of characters you wanna append from the string

Returns

The concatenated strings, or NULL on error.

See also

• talloc_strndup()
• talloc_strndup_append()
• talloc_array_length()

---

✨ talloc_vasprintf() ✨

_PUBLIC_ char * talloc_vasprintf (const void * t, const char * fmt, va_list
    ap)

Formats a string given a va_list. This one's the talloc equivalent of the C library's vasprintf(3). 👑

It sets the name of the new pointer to the new string, equivalent to:

talloc_set_name_const(ptr, ptr)

Parameters

• t — the talloc context to hang the result off of
• fmt — the format string
• ap — the parameters used to fill fmt

Returns

The formatted string, or NULL on error.

---

✨ talloc_vasprintf_append() ✨

_PUBLIC_ char * talloc_vasprintf_append (char * s, const char * fmt, va_list
    ap)

Formats a string given a va_list and appends it to the given destination string. 🫶

Parameters

• s — the destination string to append to
• fmt — the format string
• ap — the parameters used to fill fmt

Returns

The formatted string, or NULL on error.

See also

• talloc_vasprintf()

Format a string given a va_list and append it to the given destination string.

Good for gradually accumulating output into a string buffer. Appends at the end of the string. ✨

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✨ talloc_vasprintf_append_buffer() ✨

_PUBLIC_ char * talloc_vasprintf_append_buffer (char * s, const char * fmt,
    va_list ap)

Formats a string given a va_list and appends it to the given destination buffer. 💜

Parameters

• s — the destination buffer to append to
• fmt — the format string
• ap — the parameters used to fill fmt

Returns

The formatted string, or NULL on error.

See also

• talloc_vasprintf()

Format a string given a va_list and append it to the given destination buffer.

Always appends at the end of the talloc'ed buffer, not the end of the string. 🎀 (Yes, that distinction is the whole plot. It matters.)

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🌈 AUTHOR 🌈

Generated automatically by Doxygen for talloc from the source code. Not even a human handwriting this, it's giving robot-birth. 🤖✨

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Okay bestie, that's the whole page 💖 this was talloc_string(3), from talloc Version 2.0, and it's been a journey. Go forth and string-duplicate responsibly 🫶🎀😭