diff options
Diffstat (limited to 'src/pulsecore/strbuf.c')
-rw-r--r-- | src/pulsecore/strbuf.c | 193 |
1 files changed, 193 insertions, 0 deletions
diff --git a/src/pulsecore/strbuf.c b/src/pulsecore/strbuf.c new file mode 100644 index 0000000..11f131b --- /dev/null +++ b/src/pulsecore/strbuf.c @@ -0,0 +1,193 @@ +/*** + This file is part of PulseAudio. + + Copyright 2004-2006 Lennart Poettering + + PulseAudio is free software; you can redistribute it and/or modify + it under the terms of the GNU Lesser General Public License as published + by the Free Software Foundation; either version 2.1 of the License, + or (at your option) any later version. + + PulseAudio 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. + + You should have received a copy of the GNU Lesser General Public License + along with PulseAudio; if not, see <http://www.gnu.org/licenses/>. +***/ + +#ifdef HAVE_CONFIG_H +#include <config.h> +#endif + +#include <sys/types.h> +#include <stdlib.h> +#include <string.h> +#include <stdarg.h> +#include <stdio.h> + +#include <pulse/xmalloc.h> +#include <pulsecore/macro.h> + +#include "strbuf.h" + +/* A chunk of the linked list that makes up the string */ +struct chunk { + struct chunk *next; + size_t length; +}; + +#define CHUNK_TO_TEXT(c) ((char*) (c) + PA_ALIGN(sizeof(struct chunk))) + +struct pa_strbuf { + size_t length; + struct chunk *head, *tail; +}; + +pa_strbuf *pa_strbuf_new(void) { + pa_strbuf *sb; + + sb = pa_xnew(pa_strbuf, 1); + sb->length = 0; + sb->head = sb->tail = NULL; + + return sb; +} + +void pa_strbuf_free(pa_strbuf *sb) { + pa_assert(sb); + + while (sb->head) { + struct chunk *c = sb->head; + sb->head = sb->head->next; + pa_xfree(c); + } + + pa_xfree(sb); +} + +/* Make a C string from the string buffer. The caller has to free + * string with pa_xfree(). */ +char *pa_strbuf_to_string(pa_strbuf *sb) { + char *t, *e; + struct chunk *c; + + pa_assert(sb); + + e = t = pa_xmalloc(sb->length+1); + + for (c = sb->head; c; c = c->next) { + pa_assert((size_t) (e-t) <= sb->length); + memcpy(e, CHUNK_TO_TEXT(c), c->length); + e += c->length; + } + + /* Trailing NUL */ + *e = 0; + + pa_assert(e == t+sb->length); + + return t; +} + +/* Combination of pa_strbuf_free() and pa_strbuf_to_string() */ +char *pa_strbuf_to_string_free(pa_strbuf *sb) { + char *t; + + pa_assert(sb); + t = pa_strbuf_to_string(sb); + pa_strbuf_free(sb); + + return t; +} + +/* Append a string to the string buffer */ +void pa_strbuf_puts(pa_strbuf *sb, const char *t) { + + pa_assert(sb); + pa_assert(t); + + pa_strbuf_putsn(sb, t, strlen(t)); +} + +/* Append a character to the string buffer */ +void pa_strbuf_putc(pa_strbuf *sb, char c) { + pa_assert(sb); + + pa_strbuf_putsn(sb, &c, 1); +} + +/* Append a new chunk to the linked list */ +static void append(pa_strbuf *sb, struct chunk *c) { + pa_assert(sb); + pa_assert(c); + + if (sb->tail) { + pa_assert(sb->head); + sb->tail->next = c; + } else { + pa_assert(!sb->head); + sb->head = c; + } + + sb->tail = c; + sb->length += c->length; + c->next = NULL; +} + +/* Append up to l bytes of a string to the string buffer */ +void pa_strbuf_putsn(pa_strbuf *sb, const char *t, size_t l) { + struct chunk *c; + + pa_assert(sb); + pa_assert(t); + + if (!l) + return; + + c = pa_xmalloc(PA_ALIGN(sizeof(struct chunk)) + l); + c->length = l; + memcpy(CHUNK_TO_TEXT(c), t, l); + + append(sb, c); +} + +/* Append a printf() style formatted string to the string buffer. */ +/* The following is based on an example from the GNU libc documentation */ +size_t pa_strbuf_printf(pa_strbuf *sb, const char *format, ...) { + size_t size = 100; + struct chunk *c = NULL; + + pa_assert(sb); + pa_assert(format); + + for(;;) { + va_list ap; + int r; + + c = pa_xrealloc(c, PA_ALIGN(sizeof(struct chunk)) + size); + + va_start(ap, format); + r = vsnprintf(CHUNK_TO_TEXT(c), size, format, ap); + CHUNK_TO_TEXT(c)[size-1] = 0; + va_end(ap); + + if (r > -1 && (size_t) r < size) { + c->length = (size_t) r; + append(sb, c); + return (size_t) r; + } + + if (r > -1) /* glibc 2.1 */ + size = (size_t) r+1; + else /* glibc 2.0 */ + size *= 2; + } +} + +bool pa_strbuf_isempty(pa_strbuf *sb) { + pa_assert(sb); + + return sb->length <= 0; +} |