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authorDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:46:30 +0000
committerDaniel Baumann <daniel.baumann@progress-linux.org>2024-05-06 01:46:30 +0000
commitb5896ba9f6047e7031e2bdee0622d543e11a6734 (patch)
treefd7b460593a2fee1be579bec5697e6d887ea3421 /src/util/vstring.c
parentInitial commit. (diff)
downloadpostfix-b5896ba9f6047e7031e2bdee0622d543e11a6734.tar.xz
postfix-b5896ba9f6047e7031e2bdee0622d543e11a6734.zip
Adding upstream version 3.4.23.upstream/3.4.23upstream
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'src/util/vstring.c')
-rw-r--r--src/util/vstring.c717
1 files changed, 717 insertions, 0 deletions
diff --git a/src/util/vstring.c b/src/util/vstring.c
new file mode 100644
index 0000000..6dca236
--- /dev/null
+++ b/src/util/vstring.c
@@ -0,0 +1,717 @@
+/*++
+/* NAME
+/* vstring 3
+/* SUMMARY
+/* arbitrary-length string manager
+/* SYNOPSIS
+/* #include <vstring.h>
+/*
+/* VSTRING *vstring_alloc(len)
+/* ssize_t len;
+/*
+/* vstring_ctl(vp, type, value, ..., VSTRING_CTL_END)
+/* VSTRING *vp;
+/* int type;
+/*
+/* VSTRING *vstring_free(vp)
+/* VSTRING *vp;
+/*
+/* char *vstring_str(vp)
+/* VSTRING *vp;
+/*
+/* ssize_t VSTRING_LEN(vp)
+/* VSTRING *vp;
+/*
+/* char *vstring_end(vp)
+/* VSTRING *vp;
+/*
+/* void VSTRING_ADDCH(vp, ch)
+/* VSTRING *vp;
+/* int ch;
+/*
+/* int VSTRING_SPACE(vp, len)
+/* VSTRING *vp;
+/* ssize_t len;
+/*
+/* ssize_t vstring_avail(vp)
+/* VSTRING *vp;
+/*
+/* VSTRING *vstring_truncate(vp, len)
+/* VSTRING *vp;
+/* ssize_t len;
+/*
+/* VSTRING *vstring_set_payload_size(vp, len)
+/* VSTRING *vp;
+/* ssize_t len;
+/*
+/* void VSTRING_RESET(vp)
+/* VSTRING *vp;
+/*
+/* void VSTRING_TERMINATE(vp)
+/* VSTRING *vp;
+/*
+/* void VSTRING_SKIP(vp)
+/* VSTRING *vp;
+/*
+/* VSTRING *vstring_strcpy(vp, src)
+/* VSTRING *vp;
+/* const char *src;
+/*
+/* VSTRING *vstring_strncpy(vp, src, len)
+/* VSTRING *vp;
+/* const char *src;
+/* ssize_t len;
+/*
+/* VSTRING *vstring_strcat(vp, src)
+/* VSTRING *vp;
+/* const char *src;
+/*
+/* VSTRING *vstring_strncat(vp, src, len)
+/* VSTRING *vp;
+/* const char *src;
+/* ssize_t len;
+/*
+/* VSTRING *vstring_memcpy(vp, src, len)
+/* VSTRING *vp;
+/* const char *src;
+/* ssize_t len;
+/*
+/* VSTRING *vstring_memcat(vp, src, len)
+/* VSTRING *vp;
+/* const char *src;
+/* ssize_t len;
+/*
+/* char *vstring_memchr(vp, ch)
+/* VSTRING *vp;
+/* int ch;
+/*
+/* VSTRING *vstring_insert(vp, start, src, len)
+/* VSTRING *vp;
+/* ssize_t start;
+/* const char *src;
+/* ssize_t len;
+/*
+/* VSTRING *vstring_prepend(vp, src, len)
+/* VSTRING *vp;
+/* const char *src;
+/* ssize_t len;
+/*
+/* VSTRING *vstring_sprintf(vp, format, ...)
+/* VSTRING *vp;
+/* const char *format;
+/*
+/* VSTRING *vstring_sprintf_append(vp, format, ...)
+/* VSTRING *vp;
+/* const char *format;
+/*
+/* VSTRING *vstring_sprintf_prepend(vp, format, ...)
+/* VSTRING *vp;
+/* const char *format;
+/*
+/* VSTRING *vstring_vsprintf(vp, format, ap)
+/* VSTRING *vp;
+/* const char *format;
+/* va_list ap;
+/*
+/* VSTRING *vstring_vsprintf_append(vp, format, ap)
+/* VSTRING *vp;
+/* const char *format;
+/* va_list ap;
+/* AUXILIARY FUNCTIONS
+/* char *vstring_export(vp)
+/* VSTRING *vp;
+/*
+/* VSTRING *vstring_import(str)
+/* char *str;
+/* DESCRIPTION
+/* The functions and macros in this module implement arbitrary-length
+/* strings and common operations on those strings. The strings do not
+/* need to be null terminated and may contain arbitrary binary data.
+/* The strings manage their own memory and grow automatically when full.
+/* The optional string null terminator does not add to the string length.
+/*
+/* vstring_alloc() allocates storage for a variable-length string
+/* of at least "len" bytes. The minimal length is 1. The result
+/* is a null-terminated string of length zero.
+/*
+/* vstring_ctl() gives additional control over VSTRING behavior.
+/* The function takes a VSTRING pointer and a list of zero or
+/* more macros with zer or more arguments, terminated with
+/* CA_VSTRING_CTL_END which has none.
+/* .IP "CA_VSTRING_CTL_MAXLEN(ssize_t len)"
+/* Specifies a hard upper limit on a string's length. When the
+/* length would be exceeded, the program simulates a memory
+/* allocation problem (i.e. it terminates through msg_fatal()).
+/* This fuctionality is currently unimplemented.
+/* .IP "CA_VSTRING_CTL_EXACT (no argument)"
+/* Allocate the requested amounts, instead of rounding up.
+/* This should be used for tests only.
+/* .IP "CA_VSTRING_CTL_END (no argument)"
+/* Specifies the end of the argument list. Forgetting to terminate
+/* the argument list may cause the program to crash.
+/* .PP
+/* VSTRING_SPACE() ensures that the named string has room for
+/* "len" more characters. VSTRING_SPACE() is an unsafe macro
+/* that either returns zero or never returns.
+/*
+/* vstring_avail() returns the number of bytes that can be placed
+/* into the buffer before the buffer would need to grow.
+/*
+/* vstring_free() reclaims storage for a variable-length string.
+/* It conveniently returns a null pointer.
+/*
+/* vstring_str() is a macro that returns the string value
+/* of a variable-length string. It is a safe macro that
+/* evaluates its argument only once.
+/*
+/* VSTRING_LEN() is a macro that returns the current length of
+/* its argument (i.e. the distance from the start of the string
+/* to the current write position). VSTRING_LEN() is an unsafe macro
+/* that evaluates its argument more than once.
+/*
+/* vstring_end() is a macro that returns the current write position of
+/* its argument. It is a safe macro that evaluates its argument only once.
+/*
+/* VSTRING_ADDCH() adds a character to a variable-length string
+/* and extends the string if it fills up. \fIvs\fP is a pointer
+/* to a VSTRING structure; \fIch\fP the character value to be written.
+/* The result is the written character.
+/* Note that VSTRING_ADDCH() is an unsafe macro that evaluates some
+/* arguments more than once. The result is NOT null-terminated.
+/*
+/* vstring_truncate() truncates the named string to the specified
+/* length. If length is negative, the trailing portion is kept.
+/* The operation has no effect when the string is shorter.
+/* The string is not null-terminated.
+/*
+/* vstring_set_payload_size() sets the number of 'used' bytes
+/* in the named buffer's metadata. This determines the buffer
+/* write position and the VSTRING_LEN() result. The payload
+/* size must be within the closed range [0, number of allocated
+/* bytes]. The typical usage is to request buffer space with
+/* VSTRING_SPACE(), to use some non-VSTRING operations to write
+/* to the buffer, and to call vstring_set_payload_size() to
+/* update buffer metadata, perhaps followed by VSTRING_TERMINATE().
+/*
+/* VSTRING_RESET() is a macro that resets the write position of its
+/* string argument to the very beginning. Note that VSTRING_RESET()
+/* is an unsafe macro that evaluates some arguments more than once.
+/* The result is NOT null-terminated.
+/*
+/* VSTRING_TERMINATE() null-terminates its string argument.
+/* VSTRING_TERMINATE() is an unsafe macro that evaluates some
+/* arguments more than once.
+/* VSTRING_TERMINATE() does not return an interesting result.
+/*
+/* VSTRING_SKIP() is a macro that moves the write position to the first
+/* null byte after the current write position. VSTRING_SKIP() is an unsafe
+/* macro that evaluates some arguments more than once.
+/*
+/* vstring_strcpy() copies a null-terminated string to a variable-length
+/* string. \fIsrc\fP provides the data to be copied; \fIvp\fP is the
+/* target and result value. The result is null-terminated.
+/*
+/* vstring_strncpy() copies at most \fIlen\fR characters. Otherwise it is
+/* identical to vstring_strcpy().
+/*
+/* vstring_strcat() appends a null-terminated string to a variable-length
+/* string. \fIsrc\fP provides the data to be copied; \fIvp\fP is the
+/* target and result value. The result is null-terminated.
+/*
+/* vstring_strncat() copies at most \fIlen\fR characters. Otherwise it is
+/* identical to vstring_strcat().
+/*
+/* vstring_memcpy() copies \fIlen\fR bytes to a variable-length string.
+/* \fIsrc\fP provides the data to be copied; \fIvp\fP is the
+/* target and result value. The result is not null-terminated.
+/*
+/* vstring_memcat() appends \fIlen\fR bytes to a variable-length string.
+/* \fIsrc\fP provides the data to be copied; \fIvp\fP is the
+/* target and result value. The result is not null-terminated.
+/*
+/* vstring_memchr() locates a byte in a variable-length string.
+/*
+/* vstring_insert() inserts a buffer content into a variable-length
+/* string at the specified start position. The result is
+/* null-terminated.
+/*
+/* vstring_prepend() prepends a buffer content to a variable-length
+/* string. The result is null-terminated.
+/*
+/* vstring_sprintf() produces a formatted string according to its
+/* \fIformat\fR argument. See vstring_vsprintf() for details.
+/*
+/* vstring_sprintf_append() is like vstring_sprintf(), but appends
+/* to the end of the result buffer.
+/*
+/* vstring_sprintf_append() is like vstring_sprintf(), but prepends
+/* to the beginning of the result buffer.
+/*
+/* vstring_vsprintf() returns a null-terminated string according to
+/* the \fIformat\fR argument. It understands the s, c, d, u,
+/* o, x, X, p, e, f and g format types, the l modifier, field width
+/* and precision, sign, and null or space padding. This module
+/* can format strings as large as available memory permits.
+/*
+/* vstring_vsprintf_append() is like vstring_vsprintf(), but appends
+/* to the end of the result buffer.
+/*
+/* In addition to stdio-like format specifiers, vstring_vsprintf()
+/* recognizes %m and expands it to the corresponding errno text.
+/*
+/* vstring_export() extracts the string value from a VSTRING.
+/* The VSTRING is destroyed. The result should be passed to myfree().
+/*
+/* vstring_import() takes a `bare' string and converts it to
+/* a VSTRING. The string argument must be obtained from mymalloc().
+/* The string argument is not copied.
+/* DIAGNOSTICS
+/* Fatal errors: memory allocation failure.
+/* BUGS
+/* Auto-resizing may change the address of the string data in
+/* a vstring structure. Beware of dangling pointers.
+/* HISTORY
+/* .ad
+/* .fi
+/* A vstring module appears in the UNPROTO software by Wietse Venema.
+/* AUTHOR(S)
+/* Wietse Venema
+/* IBM T.J. Watson Research
+/* P.O. Box 704
+/* Yorktown Heights, NY 10598, USA
+/*
+/* Wietse Venema
+/* Google, Inc.
+/* 111 8th Avenue
+/* New York, NY 10011, USA
+/*--*/
+
+/* System libraries. */
+
+#include <sys_defs.h>
+#include <stddef.h>
+#include <stdlib.h> /* 44BSD stdarg.h uses abort() */
+#include <stdarg.h>
+#include <string.h>
+
+/* Utility library. */
+
+#define VSTRING_INTERNAL
+
+#include "mymalloc.h"
+#include "msg.h"
+#include "vbuf_print.h"
+#include "vstring.h"
+
+/* vstring_extend - variable-length string buffer extension policy */
+
+static void vstring_extend(VBUF *bp, ssize_t incr)
+{
+ size_t used = bp->ptr - bp->data;
+ ssize_t new_len;
+
+ /*
+ * Note: vp->vbuf.len is the current buffer size (both on entry and on
+ * exit of this routine). We round up the increment size to the buffer
+ * size to avoid silly little buffer increments. With really large
+ * strings we might want to abandon the length doubling strategy, and go
+ * to fixed increments.
+ *
+ * The length overflow tests here and in vstring_alloc() should protect us
+ * against all length overflow problems within vstring library routines.
+ *
+ * Safety net: add a gratuitous null terminator so that C-style string
+ * operations won't scribble past the end.
+ */
+ if ((bp->flags & VSTRING_FLAG_EXACT) == 0 && bp->len > incr)
+ incr = bp->len;
+ if (bp->len > SSIZE_T_MAX - incr - 1)
+ msg_fatal("vstring_extend: length overflow");
+ new_len = bp->len + incr;
+ bp->data = (unsigned char *) myrealloc((void *) bp->data, new_len + 1);
+ bp->data[new_len] = 0;
+ bp->len = new_len;
+ bp->ptr = bp->data + used;
+ bp->cnt = bp->len - used;
+}
+
+/* vstring_buf_get_ready - vbuf callback for read buffer empty condition */
+
+static int vstring_buf_get_ready(VBUF *unused_buf)
+{
+ return (VBUF_EOF); /* be VSTREAM-friendly */
+}
+
+/* vstring_buf_put_ready - vbuf callback for write buffer full condition */
+
+static int vstring_buf_put_ready(VBUF *bp)
+{
+ vstring_extend(bp, 1);
+ return (0);
+}
+
+/* vstring_buf_space - vbuf callback to reserve space */
+
+static int vstring_buf_space(VBUF *bp, ssize_t len)
+{
+ ssize_t need;
+
+ if (len < 0)
+ msg_panic("vstring_buf_space: bad length %ld", (long) len);
+ if ((need = len - bp->cnt) > 0)
+ vstring_extend(bp, need);
+ return (0);
+}
+
+/* vstring_alloc - create variable-length string */
+
+VSTRING *vstring_alloc(ssize_t len)
+{
+ VSTRING *vp;
+
+ /*
+ * Safety net: add a gratuitous null terminator so that C-style string
+ * operations won't scribble past the end.
+ */
+ if (len < 1 || len > SSIZE_T_MAX - 1)
+ msg_panic("vstring_alloc: bad length %ld", (long) len);
+ vp = (VSTRING *) mymalloc(sizeof(*vp));
+ vp->vbuf.flags = 0;
+ vp->vbuf.len = 0;
+ vp->vbuf.data = (unsigned char *) mymalloc(len + 1);
+ vp->vbuf.data[len] = 0;
+ vp->vbuf.len = len;
+ VSTRING_RESET(vp);
+ vp->vbuf.data[0] = 0;
+ vp->vbuf.get_ready = vstring_buf_get_ready;
+ vp->vbuf.put_ready = vstring_buf_put_ready;
+ vp->vbuf.space = vstring_buf_space;
+ return (vp);
+}
+
+/* vstring_free - destroy variable-length string */
+
+VSTRING *vstring_free(VSTRING *vp)
+{
+ if (vp->vbuf.data)
+ myfree((void *) vp->vbuf.data);
+ myfree((void *) vp);
+ return (0);
+}
+
+/* vstring_ctl - modify memory management policy */
+
+void vstring_ctl(VSTRING *vp,...)
+{
+ va_list ap;
+ int code;
+
+ va_start(ap, vp);
+ while ((code = va_arg(ap, int)) != VSTRING_CTL_END) {
+ switch (code) {
+ default:
+ msg_panic("vstring_ctl: unknown code: %d", code);
+ case VSTRING_CTL_EXACT:
+ vp->vbuf.flags |= VSTRING_FLAG_EXACT;
+ break;
+ }
+ }
+ va_end(ap);
+}
+
+/* vstring_truncate - truncate string */
+
+VSTRING *vstring_truncate(VSTRING *vp, ssize_t len)
+{
+ ssize_t move;
+
+ if (len < 0) {
+ len = (-len);
+ if ((move = VSTRING_LEN(vp) - len) > 0)
+ memmove(vstring_str(vp), vstring_str(vp) + move, len);
+ }
+ if (len < VSTRING_LEN(vp))
+ VSTRING_AT_OFFSET(vp, len);
+ return (vp);
+}
+
+/* vstring_set_payload_size - public version of VSTRING_AT_OFFSET */
+
+VSTRING *vstring_set_payload_size(VSTRING *vp, ssize_t len)
+{
+ if (len < 0 || len > vp->vbuf.len)
+ msg_panic("vstring_set_payload_size: invalid offset: %ld", (long) len);
+ VSTRING_AT_OFFSET(vp, len);
+ return (vp);
+}
+
+/* vstring_strcpy - copy string */
+
+VSTRING *vstring_strcpy(VSTRING *vp, const char *src)
+{
+ VSTRING_RESET(vp);
+
+ while (*src) {
+ VSTRING_ADDCH(vp, *src);
+ src++;
+ }
+ VSTRING_TERMINATE(vp);
+ return (vp);
+}
+
+/* vstring_strncpy - copy string of limited length */
+
+VSTRING *vstring_strncpy(VSTRING *vp, const char *src, ssize_t len)
+{
+ VSTRING_RESET(vp);
+
+ while (len-- > 0 && *src) {
+ VSTRING_ADDCH(vp, *src);
+ src++;
+ }
+ VSTRING_TERMINATE(vp);
+ return (vp);
+}
+
+/* vstring_strcat - append string */
+
+VSTRING *vstring_strcat(VSTRING *vp, const char *src)
+{
+ while (*src) {
+ VSTRING_ADDCH(vp, *src);
+ src++;
+ }
+ VSTRING_TERMINATE(vp);
+ return (vp);
+}
+
+/* vstring_strncat - append string of limited length */
+
+VSTRING *vstring_strncat(VSTRING *vp, const char *src, ssize_t len)
+{
+ while (len-- > 0 && *src) {
+ VSTRING_ADDCH(vp, *src);
+ src++;
+ }
+ VSTRING_TERMINATE(vp);
+ return (vp);
+}
+
+/* vstring_memcpy - copy buffer of limited length */
+
+VSTRING *vstring_memcpy(VSTRING *vp, const char *src, ssize_t len)
+{
+ VSTRING_RESET(vp);
+
+ VSTRING_SPACE(vp, len);
+ memcpy(vstring_str(vp), src, len);
+ VSTRING_AT_OFFSET(vp, len);
+ return (vp);
+}
+
+/* vstring_memcat - append buffer of limited length */
+
+VSTRING *vstring_memcat(VSTRING *vp, const char *src, ssize_t len)
+{
+ VSTRING_SPACE(vp, len);
+ memcpy(vstring_end(vp), src, len);
+ len += VSTRING_LEN(vp);
+ VSTRING_AT_OFFSET(vp, len);
+ return (vp);
+}
+
+/* vstring_memchr - locate byte in buffer */
+
+char *vstring_memchr(VSTRING *vp, int ch)
+{
+ unsigned char *cp;
+
+ for (cp = (unsigned char *) vstring_str(vp); cp < (unsigned char *) vstring_end(vp); cp++)
+ if (*cp == ch)
+ return ((char *) cp);
+ return (0);
+}
+
+/* vstring_insert - insert text into string */
+
+VSTRING *vstring_insert(VSTRING *vp, ssize_t start, const char *buf, ssize_t len)
+{
+ ssize_t new_len;
+
+ /*
+ * Sanity check.
+ */
+ if (start < 0 || start >= VSTRING_LEN(vp))
+ msg_panic("vstring_insert: bad start %ld", (long) start);
+ if (len < 0)
+ msg_panic("vstring_insert: bad length %ld", (long) len);
+
+ /*
+ * Move the existing content and copy the new content.
+ */
+ new_len = VSTRING_LEN(vp) + len;
+ VSTRING_SPACE(vp, len);
+ memmove(vstring_str(vp) + start + len, vstring_str(vp) + start,
+ VSTRING_LEN(vp) - start);
+ memcpy(vstring_str(vp) + start, buf, len);
+ VSTRING_AT_OFFSET(vp, new_len);
+ VSTRING_TERMINATE(vp);
+ return (vp);
+}
+
+/* vstring_prepend - prepend text to string */
+
+VSTRING *vstring_prepend(VSTRING *vp, const char *buf, ssize_t len)
+{
+ ssize_t new_len;
+
+ /*
+ * Sanity check.
+ */
+ if (len < 0)
+ msg_panic("vstring_prepend: bad length %ld", (long) len);
+
+ /*
+ * Move the existing content and copy the new content.
+ */
+ new_len = VSTRING_LEN(vp) + len;
+ VSTRING_SPACE(vp, len);
+ memmove(vstring_str(vp) + len, vstring_str(vp), VSTRING_LEN(vp));
+ memcpy(vstring_str(vp), buf, len);
+ VSTRING_AT_OFFSET(vp, new_len);
+ VSTRING_TERMINATE(vp);
+ return (vp);
+}
+
+/* vstring_export - VSTRING to bare string */
+
+char *vstring_export(VSTRING *vp)
+{
+ char *cp;
+
+ cp = (char *) vp->vbuf.data;
+ vp->vbuf.data = 0;
+ myfree((void *) vp);
+ return (cp);
+}
+
+/* vstring_import - bare string to vstring */
+
+VSTRING *vstring_import(char *str)
+{
+ VSTRING *vp;
+ ssize_t len;
+
+ vp = (VSTRING *) mymalloc(sizeof(*vp));
+ len = strlen(str);
+ vp->vbuf.flags = 0;
+ vp->vbuf.len = 0;
+ vp->vbuf.data = (unsigned char *) str;
+ vp->vbuf.len = len + 1;
+ VSTRING_AT_OFFSET(vp, len);
+ vp->vbuf.get_ready = vstring_buf_get_ready;
+ vp->vbuf.put_ready = vstring_buf_put_ready;
+ vp->vbuf.space = vstring_buf_space;
+ return (vp);
+}
+
+/* vstring_sprintf - formatted string */
+
+VSTRING *vstring_sprintf(VSTRING *vp, const char *format,...)
+{
+ va_list ap;
+
+ va_start(ap, format);
+ vp = vstring_vsprintf(vp, format, ap);
+ va_end(ap);
+ return (vp);
+}
+
+/* vstring_vsprintf - format string, vsprintf-like interface */
+
+VSTRING *vstring_vsprintf(VSTRING *vp, const char *format, va_list ap)
+{
+ VSTRING_RESET(vp);
+ vbuf_print(&vp->vbuf, format, ap);
+ VSTRING_TERMINATE(vp);
+ return (vp);
+}
+
+/* vstring_sprintf_append - append formatted string */
+
+VSTRING *vstring_sprintf_append(VSTRING *vp, const char *format,...)
+{
+ va_list ap;
+
+ va_start(ap, format);
+ vp = vstring_vsprintf_append(vp, format, ap);
+ va_end(ap);
+ return (vp);
+}
+
+/* vstring_vsprintf_append - format + append string, vsprintf-like interface */
+
+VSTRING *vstring_vsprintf_append(VSTRING *vp, const char *format, va_list ap)
+{
+ vbuf_print(&vp->vbuf, format, ap);
+ VSTRING_TERMINATE(vp);
+ return (vp);
+}
+
+/* vstring_sprintf_prepend - format + prepend string, vsprintf-like interface */
+
+VSTRING *vstring_sprintf_prepend(VSTRING *vp, const char *format,...)
+{
+ va_list ap;
+ ssize_t old_len = VSTRING_LEN(vp);
+ ssize_t result_len;
+
+ /* Construct: old|new|free */
+ va_start(ap, format);
+ vp = vstring_vsprintf_append(vp, format, ap);
+ va_end(ap);
+ result_len = VSTRING_LEN(vp);
+
+ /* Construct: old|new|old|free */
+ VSTRING_SPACE(vp, old_len);
+ vstring_memcat(vp, vstring_str(vp), old_len);
+
+ /* Construct: new|old|free */
+ memmove(vstring_str(vp), vstring_str(vp) + old_len, result_len);
+ VSTRING_AT_OFFSET(vp, result_len);
+ VSTRING_TERMINATE(vp);
+ return (vp);
+}
+
+#ifdef TEST
+
+ /*
+ * Test program - concatenate all command-line arguments into one string.
+ */
+#include <stdio.h>
+
+int main(int argc, char **argv)
+{
+ VSTRING *vp = vstring_alloc(1);
+ int n;
+
+ /*
+ * Report the location of the gratuitous null terminator.
+ */
+ for (n = 1; n <= 5; n++) {
+ VSTRING_ADDCH(vp, 'x');
+ printf("payload/buffer size %d/%ld, strlen() %ld\n",
+ n, (long) (vp)->vbuf.len, (long) strlen(vstring_str(vp)));
+ }
+
+ VSTRING_RESET(vp);
+ while (argc-- > 0) {
+ vstring_strcat(vp, *argv++);
+ vstring_strcat(vp, ".");
+ }
+ printf("argv concatenated: %s\n", vstring_str(vp));
+ vstring_free(vp);
+ return (0);
+}
+
+#endif