From: Gregor Beck Date: Wed, 29 Sep 2010 12:49:40 +0000 (+0200) Subject: s3-lib: add cbuf, a talloced character buffer X-Git-Url: http://git.samba.org/?p=obnox%2Fsamba-ctdb.git;a=commitdiff_plain;h=e9d313880a6596fbf7fea5bda4e147aeaba02eb8 s3-lib: add cbuf, a talloced character buffer --- diff --git a/source3/Makefile.in b/source3/Makefile.in index 4430f0ed30..005e4c21fa 100644 --- a/source3/Makefile.in +++ b/source3/Makefile.in @@ -941,7 +941,8 @@ NET_OBJ1 = utils/net.o utils/net_ads.o utils/net_help.o \ auth/token_util.o utils/net_dom.o utils/net_share.o \ utils/net_g_lock.o \ utils/net_serverid.o \ - utils/net_eventlog.o + utils/net_eventlog.o \ + lib/cbuf.o # these are not processed by make proto NET_OBJ2 = utils/net_registry_util.o utils/net_help_common.o diff --git a/source3/lib/cbuf.c b/source3/lib/cbuf.c new file mode 100644 index 0000000000..3cd164a574 --- /dev/null +++ b/source3/lib/cbuf.c @@ -0,0 +1,287 @@ +/* + * Samba Unix/Linux SMB client library + * + * Copyright (C) Gregor Beck 2010 + * + * 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. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +/** + * @file cbuf.c + * @author Gregor Beck + * @date Aug 2010 + * + * @brief A talloced character buffer. + * + */ + + +#include +#include "includes.h" +#include "cbuf.h" + + +struct cbuf { + char* buf; + size_t pos; + size_t size; +}; + + +cbuf* cbuf_clear(cbuf* b) +{ + cbuf_setpos(b, 0); + return b; +} + +cbuf* cbuf_new(const void* ctx) +{ + cbuf* s = talloc(ctx, cbuf); + if (s == NULL) + return NULL; + s->size = 32; + s->buf = talloc_size(s, s->size); + if (s->size && (s->buf == NULL)) { + talloc_free(s); + return NULL; + } + return cbuf_clear(s); +} + +cbuf* cbuf_copy(const cbuf* b) +{ + cbuf* s = talloc(talloc_parent(b), cbuf); + if (s == NULL) { + return NULL; + } + + s->buf = talloc_memdup(s, b->buf, b->size); /* only up to pos? */ + + /* XXX shallow did not work, because realloc */ + /* fails with multiple references */ + /* s->buf = talloc_reference(s, b->buf); */ + + if (s->buf == NULL) { + cbuf_delete(s); + return NULL; + } + s->size = b->size; + s->pos = b->pos; + return s; +} + +void cbuf_delete(cbuf* b) +{ + talloc_free(b); +} + +#define SWAP(A,B,T) do { \ + T tmp = A; A = B; B = tmp; \ + } while(0) + + +void cbuf_swap(cbuf* b1, cbuf* b2) +{ + if (b1 == b2) { + return; + } + talloc_steal(b2, b1->buf); + talloc_steal(b1, b2->buf); + SWAP(b1->buf, b2->buf, char*); + SWAP(b1->pos, b2->pos, size_t); + SWAP(b1->size, b2->size, size_t); +} + + + +cbuf* cbuf_takeover(cbuf* b1, cbuf* b2) +{ + talloc_steal(b1, b2->buf); + b1->buf = b2->buf; + b1->pos = b2->pos; + b1->size = b2->size; + cbuf_delete(b2); + return b1; +} + +cbuf* cbuf_swapptr(cbuf* b, char** ptr, size_t len) +{ + SWAP(b->buf, *ptr, char*); + talloc_steal(b, b->buf); + b->size = talloc_get_size(b->buf); + b->pos = (len == -1) ? strlen(b->buf) : len; + + assert(b->pos <= b->size); + return b; +} + +cbuf* cbuf_resize(cbuf* b, size_t size) +{ + char* save_buf = b->buf; + b->buf = talloc_realloc(b, b->buf, char, size); + if (b->buf == NULL) { + talloc_free(save_buf); + b->size = 0; + } else { + b->size = size; + } + b->pos = MIN(b->pos, b->size); + return b->buf ? b : NULL; +} + +char* cbuf_reserve(cbuf* b, size_t len) +{ + if(b->size < b->pos + len) + cbuf_resize(b, MAX(2*b->size, b->pos + len)); + return b->buf ? b->buf + b->pos : NULL; +} + +int cbuf_puts(cbuf* b, const char* str, size_t len) +{ + char* dst; + + if (b == NULL) + return 0; + + if (len == -1) { + len=strlen(str); + } + + dst = cbuf_reserve(b, len+1); + if (dst == NULL) + return -1; + + memcpy(dst, str, len); + dst[len] = '\0'; /* just to ease debugging */ + + b->pos += len; + assert(b->pos < b->size); + + return len; +} + +int cbuf_putc(cbuf* b, char c) { + char* dst; + + if (b == NULL) + return 0; + + dst = cbuf_reserve(b, 2); + if (dst == NULL) { + return -1; + } + + dst[0] = c; + dst[1] = '\0'; /* just to ease debugging */ + + b->pos++; + assert(b->pos < b->size); + + return 1; +} + +int cbuf_putdw(cbuf* b, uint32_t u) { + char* dst; + static const size_t LEN = sizeof(uint32_t); + + if (b == NULL) + return 0; + + dst = cbuf_reserve(b, LEN); + if (dst == NULL) { + return -1; + } + + SIVAL(dst, 0, u); + + b->pos += LEN; + assert(b->pos <= b->size); /* no NULL termination*/ + + return LEN; +} + +size_t cbuf_getpos(const cbuf* b) { + assert(b->pos <= b->size); + return b->pos; +} + +void cbuf_setpos(cbuf* b, size_t pos) { + assert(pos <= b->size); + b->pos = pos; + if (pos < b->size) + b->buf[pos] = '\0'; /* just to ease debugging */ +} + +char* cbuf_gets(cbuf* b, size_t idx) { + assert(idx <= b->pos); + + if (cbuf_reserve(b, 1) == NULL) + return NULL; + + b->buf[b->pos] = '\0'; + return b->buf + idx; +} + +int cbuf_printf(cbuf* b, const char* fmt, ...) +{ + va_list args, args2; + int len; + char* dst = b->buf + b->pos; + const int avail = b->size - b->pos; + assert(avail >= 0); + + va_start(args, fmt); + va_copy(args2, args); + + len = vsnprintf(dst, avail, fmt, args); + + if (len >= avail) { + dst = cbuf_reserve(b, len+1); + len = (dst != NULL) ? vsnprintf(dst, len+1, fmt, args2) : -1; + } + + if (len > 0) { + b->pos += len; + } + + va_end(args); + va_end(args2); + assert(b->pos <= b->size); + + return len; +} + +int cbuf_print_quoted_string(cbuf* ost, const char* s) +{ + int n = 1; + cbuf_putc(ost,'"'); + + while(true) { + switch (*s) { + case '\0': + cbuf_putc(ost, '"'); + return n+1; + + case '"': + case '\\': + cbuf_putc(ost, '\\'); + n++; + /* no break */ + default: + cbuf_putc(ost, *s); + n++; + } + s++; + } +} diff --git a/source3/lib/cbuf.h b/source3/lib/cbuf.h new file mode 100644 index 0000000000..ffb52d7b9a --- /dev/null +++ b/source3/lib/cbuf.h @@ -0,0 +1,235 @@ +/* + * Samba Unix/Linux SMB client library + * Copyright (C) Gregor Beck 2010 + * + * 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. + * + * 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. + * + * You should have received a copy of the GNU General Public License + * along with this program. If not, see . + */ + +/** + * @file cbuf.h + * @author Gregor Beck + * @date Aug 2010 + * + * @brief A talloced character buffer. + * + * A cbuf carries a write position and keeps track of its size. + */ + +#ifndef __CBUF_H +#define __CBUF_H + +#include +#include +#include + + +struct cbuf; +typedef struct cbuf cbuf; + +/** + * Create a new character buffer. + * + * @param talloc_ctx the talloc parent + * + * @return a new cbuf object, NULL on error + */ +cbuf* cbuf_new(const void* talloc_ctx); + +/** + * Create a copy of a character buffer. + * + * @param b the cbuf to copy + * @return a new cbuf object, NULL on error + */ +cbuf* cbuf_copy(const cbuf* b); + +/** + * Delete a character buffer. + * This invalidates b and free's the memory allocated. + * @warning don't talloc_free b directly, however freeing + * the parent works as expected + * @param b the cbuf to delete + */ +void cbuf_delete(cbuf* b); + +/** + * Reset the buffer to initial state. + * Set the write positon to the start of buffer, effectivly + * clearing its contents. Doesn't free memory. + * + * @param b the buffer to clear + * + * @return b + */ +cbuf* cbuf_clear(cbuf* b); + +/** + * Swap the contents of two buffers in O(1). + * + * @param b1 a character buffer + * @param b2 another character buffer + */ +void cbuf_swap(cbuf* b1, cbuf* b2); + +/** + * Swap the contents of a buffer with a talloced string. + * + * @param b a character buffer + * @param ptr a pointer to a talloced string + * @param len size of string, -1 means strlen(*ptr) + * + * @return b + */ +cbuf* cbuf_swapptr(cbuf* b, char** ptr, size_t len); + +/** + * Let a character buffer takeover the contents of another. + * This is equivalent to @code + * cbuf_swap(b1, b2); + * cbuf_delete(b2); + * @endcode + * @param b1 the destination + * @param b2 the victim + * + * @return b1 + */ +cbuf* cbuf_takeover(cbuf* b1, cbuf* b2); + +/** + * Resize a character buffer. + * This may free allocated memory. + * + * @param b the character buffer. + * @param size the new size + * + * @return b, NULL on error + */ +cbuf* cbuf_resize(cbuf* b, size_t size); + +/** + * Reserve space in a character buffer. + * Assert there are at least len bytes following the current write position. + * + * @param b a character buffer + * @param len number of bytes to reserve. + * + * @return a pointer to the current write position, NULL on error + */ +char* cbuf_reserve(cbuf* b, size_t len); + +/** + * Put a character into the buffer. + * + * @param b a charcter buffer, may be NULL. + * @param c a character + * @return number of charcters written ((b==NULL) ? 0 : 1) + * + * @retval -1 on error + */ +int cbuf_putc(cbuf* b, char c); + +/** + * Put a string into the buffer. + * + * @param b a character buffer, may be NULL + * @param str a string + * @param len number of bytes to write, -1 means strlen(str) + * + * @return number of characters written, -1 on error + */ +int cbuf_puts(cbuf* b, const char* str, size_t len); + +/* /\** */ +/* * Put a string into the buffer, changing case. */ +/* * */ +/* * @param b a character buffer, may be NULL */ +/* * @param str a string */ +/* * @param len number of bytes to write, -1 means strlen(str) */ +/* * @param c a character specifying case: */ +/* * @li 'U' upper case */ +/* * @li 'L' lower case */ +/* * @li 'T' title case */ +/* * @li 'P' preserve case */ +/* * @return number of characters written, -1 on error */ +/* *\/ */ +/* int cbuf_puts_case(cbuf* b, const char* str, size_t len, char c); */ + + + +/** + * Put a uint32 into the buffer. + * Write in little endian order. + * + * @param b a character buffer, may be NULL + * @param u an uint32 + * + * @return number of characters written, -1 on error + */ +int cbuf_putdw(cbuf* b, uint32_t u); + +/** + * Print formated to a character buffer. + * + * @param b a charcter buffer + * @param fmt a printf format string + * + * @return number of characters written, negative on error + */ +int cbuf_printf(cbuf* b, const char* fmt, ...); + + +/** + * Get the current write position. + * + * @param b a character buffer. + * + * @return index of the next charcter to write. + */ +size_t cbuf_getpos(const cbuf* b); + +/** + * Set the current write position of a buffer. + * Invalidates the buffer contents from on the new position. + * + * @param b a charcter buffer + * @param pos a position obtained by cbuf_getpos + */ +void cbuf_setpos(cbuf* b, size_t pos); + +/** + * Get the buffer contents + * starting at idx. + * @pre @code idx <= cbuf_getpos(b) @endcode + * @param b a character buffer + * @param idx a position obtained by cbuf_getpos + * + * @return a NUL terminated string + */ +char* cbuf_gets(cbuf* b, size_t idx); + +/** + * Print quoted string to stream. + * + * @todo check for ssputc failure + * @see srprs_quoted_string + * + * @param[out] ost outstream + * @param[in] s string + * + * @return numner of bytes written, -1 on error + */ +int cbuf_print_quoted_string(cbuf* ost, const char* s); + + +#endif /*__CBUF_H*/