Move stuff around and add initial autotools files.

6 files changed, 2033 insertions, 0 deletions

diff --git a/Makefile.am b/Makefile.am
new file mode 100644
index 0000000..f268924
--- /dev/null
+++ b/Makefile.am
@@ -0,0 +1,2 @@
+SUBDIRS = src
+
diff --git a/configure.ac b/configure.ac
new file mode 100644
index 0000000..a8a67b3
--- /dev/null
+++ b/configure.ac
@@ -0,0 +1,7 @@
+AC_INIT([dynstr], [0.0], [liw@liw.fi])
+AM_INIT_AUTOMAKE([foreign -Wall -Werror])
+AC_PROG_CC_C99
+AC_CONFIG_HEADERS([config.h])
+AC_CONFIG_FILES([Makefile src/Makefile])
+AC_OUTPUT
+
diff --git a/src/Makefile.am b/src/Makefile.am
new file mode 100644
index 0000000..657e3e6
--- /dev/null
+++ b/src/Makefile.am
@@ -0,0 +1,3 @@
+bin_PROGRAMS = unittests
+unittests_SOURCES = unittests.c dynstr.c
+
diff --git a/src/dynstr.c b/src/dynstr.c
new file mode 100644
index 0000000..44c4b56
--- /dev/null
+++ b/src/dynstr.c
@@ -0,0 +1,547 @@
+/*
+ * dynstr.c - implement dynamic byte strings
+ * Copyright 2010  Lars Wirzenius
+ * 
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+
+/* We shamelessly use GNU extensions to the standard C library.
+ * Primarily this is the memmem(3) function. Patches are welcome to
+ * get rid of this, but I did not feel like re-inventing the wheel.
+ */
+#define _GNU_SOURCE
+
+#include <errno.h>
+#include <stdbool.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include "dynstr.h"
+
+
+/* This is how the dynamic strings are represented. */
+struct Dynstr {
+    unsigned char *mem;
+    size_t size;
+};
+
+
+/* Return value for readline_helper's callback functions. */
+#define DYNSTR_ERROR ((size_t) -1)
+
+
+/* The current malloc and malloc error handler functions. */
+static dynstr_error_handler *error_handler = dynstr_malloc_error_indicate;
+static void *(*current_malloc)(size_t) = malloc;
+
+
+void dynstr_init(void)
+{
+    error_handler = dynstr_malloc_error_indicate;
+    current_malloc = malloc;
+}
+
+
+void *(*dynstr_get_malloc(void))(size_t)
+{
+    return current_malloc;
+}
+
+
+void dynstr_set_malloc(void *(*new_malloc)(size_t))
+{
+    current_malloc = new_malloc;
+}
+
+
+dynstr_error_handler *dynstr_get_malloc_error_handler(void)
+{
+    return error_handler;
+}
+
+
+void dynstr_set_malloc_error_handler(dynstr_error_handler *handler)
+{
+    error_handler = handler;
+}
+
+
+void dynstr_malloc_error_indicate(int error, size_t size, void *oldptr)
+{
+}
+
+void dynstr_malloc_error_abort(int error, size_t size, void *oldptr)
+{
+    abort();
+}
+
+
+/* Dynamically allocate a number of bytes. Call error handler if necessary. */
+static void *alloc(size_t size)
+{
+    void *p;
+    
+    p = current_malloc(size);
+    if (p == NULL)
+        error_handler(errno, size, NULL);
+    return p;
+}
+
+
+static Dynstr *new_dynstr(const void *mem, size_t size, bool dynamic)
+{
+    Dynstr *dynstr;
+    
+    if (dynamic) {
+        dynstr = alloc(sizeof(Dynstr) + size);
+        if (dynstr == NULL)
+            return NULL;
+        dynstr->mem = ((unsigned char *) dynstr) + sizeof(Dynstr);
+    } else {
+        dynstr = alloc(sizeof(Dynstr));
+        if (dynstr == NULL)
+            return NULL;
+        dynstr->mem = (unsigned char *) mem;
+    }
+
+    dynstr->size = size;
+    return dynstr;
+}
+
+
+static void init_dynstr(Dynstr *dynstr, const void *mem, bool dynamic)
+{
+    if (dynamic)
+        memcpy(dynstr->mem, mem, dynstr->size);
+}
+
+
+/* Allocate a new dynamic string. If dynamic is true, the contents of the
+ * new string is copied from mem. Otherwise the new string just uses mem
+ * directly. */
+static Dynstr *newstr(const void *mem, size_t size, bool dynamic)
+{
+    Dynstr *dynstr;
+    
+    dynstr = new_dynstr(mem, size, dynamic);
+    if (dynstr != NULL)
+        init_dynstr(dynstr, mem, dynamic);
+    return dynstr;
+}
+
+
+Dynstr *dynstr_new_empty(void)
+{
+    return new_dynstr(NULL, 0, false);
+}
+
+
+Dynstr *dynstr_new_from_cstring(const char *cstring)
+{
+    return newstr(cstring, strlen(cstring), true);
+}
+
+
+Dynstr *dynstr_new_from_memory(const void *mem, size_t size)
+{
+    return newstr(mem, size, true);
+}
+
+
+Dynstr *dynstr_new_from_constant_cstring(const char *cstring)
+{
+    return newstr(cstring, strlen(cstring), false);
+}
+
+
+Dynstr *dynstr_new_from_constant_memory(const void *mem, size_t size)
+{
+    return newstr(mem, size, false);
+}
+
+
+void dynstr_free(Dynstr *dynstr)
+{
+    free(dynstr);
+}
+
+
+size_t dynstr_len(Dynstr *dynstr)
+{
+    return dynstr->size;
+}
+
+
+bool dynstr_is_empty(Dynstr *dynstr)
+{
+    return dynstr_len(dynstr) == 0;
+}
+
+
+size_t dynstr_memcpy(void *mem, Dynstr *dynstr, size_t offset, size_t size)
+{
+    size_t len;
+    
+    len = dynstr_len(dynstr);
+    if (offset >= len)
+        return 0;
+    if (size > len - offset)
+        size = len - offset;
+    memcpy(mem, dynstr->mem + offset, size);
+    return size;
+}
+
+
+char *dynstr_strdup(Dynstr *dynstr)
+{
+    char *mem;
+    
+    mem = alloc(dynstr->size + 1);
+    if (mem == NULL)
+        return NULL;
+    memcpy(mem, dynstr->mem, dynstr->size);
+    mem[dynstr->size] = '\0';
+    return mem;
+}
+
+
+Dynstr *dynstr_substr(Dynstr *dynstr, size_t offset, size_t size)
+{
+    if (offset >= dynstr->size) {
+        offset = 0;
+        size = 0;
+    } else if (size > dynstr->size - offset) {
+        size = dynstr->size - offset;
+    }
+    return newstr(dynstr->mem + offset, size, true);
+}
+
+
+Dynstr *dynstr_cat(Dynstr *dynstr1, Dynstr *dynstr2)
+{
+    return dynstr_cat_many(dynstr1, dynstr2, (Dynstr *) NULL);
+}
+
+
+Dynstr *dynstr_cat_many(Dynstr *dynstr, ...)
+{
+    va_list args;
+    Dynstr *result;
+    size_t size;
+    size_t offset;
+    
+    va_start(args, dynstr);
+    size = 0;
+    for (Dynstr *p = dynstr; p != NULL; p = va_arg(args, Dynstr *))
+        size += p->size;
+    va_end(args);
+    
+    result = new_dynstr(NULL, size, true);
+    if (result == NULL)
+        return NULL;
+
+    va_start(args, dynstr);
+    offset = 0;
+    for (Dynstr *p = dynstr; p != NULL; p = va_arg(args, Dynstr *)) {
+        memcpy(result->mem + offset, p->mem, p->size);
+        offset += p->size;
+    }
+    va_end(args);
+
+    return result;
+}
+
+
+int dynstr_byte_at(Dynstr *dynstr, size_t offset)
+{
+    if (offset >= dynstr->size)
+        return -1;
+    return dynstr->mem[offset];
+}
+
+
+size_t dynstr_first_byte(Dynstr *dynstr, size_t offset, int byte)
+{
+    unsigned char *p;
+
+    if (offset >= dynstr->size)
+        return DYNSTR_NOT_FOUND;
+    p = memchr(dynstr->mem + offset, byte, dynstr->size - offset);
+    if (p == NULL)
+        return DYNSTR_NOT_FOUND;
+    return (size_t) (p - dynstr->mem);
+}
+
+
+size_t dynstr_last_byte(Dynstr *dynstr, size_t offset, int byte)
+{
+    unsigned char *p;
+
+    if (offset >= dynstr->size)
+        return DYNSTR_NOT_FOUND;
+    p = memrchr(dynstr->mem + offset, byte, dynstr->size - offset);
+    if (p == NULL)
+        return DYNSTR_NOT_FOUND;
+    return (size_t) (p - dynstr->mem);
+}
+
+
+size_t dynstr_first_string(Dynstr *dynstr, size_t offset, Dynstr *pattern)
+{
+    const unsigned char *p;
+    
+    if (offset >= dynstr->size)
+        return DYNSTR_NOT_FOUND;
+    if (pattern->size == 0)
+        return DYNSTR_NOT_FOUND;
+    p = memmem(dynstr->mem + offset, dynstr->size - offset, 
+               pattern->mem, pattern->size);
+    if (p == NULL)
+        return DYNSTR_NOT_FOUND;
+    return (size_t) (p - dynstr->mem);
+}
+
+
+size_t dynstr_last_string(Dynstr *dynstr, size_t offset, Dynstr *pattern)
+{
+    size_t result;
+    size_t new_result;
+
+    /* GNU libc lacks a memrmem function, so we loop to the last
+     * dynstr_first_string match. */
+    result = DYNSTR_NOT_FOUND;    
+    for (;;) {
+        new_result = dynstr_first_string(dynstr, offset, pattern);
+        if (new_result == DYNSTR_NOT_FOUND)
+            break;
+        result = new_result;
+        offset = result + 1;
+    }
+    return result;
+}
+
+
+int dynstr_cmp(Dynstr *dynstr1, Dynstr *dynstr2)
+{
+    int result;
+    size_t min_size;
+
+    if (dynstr1->size < dynstr2->size)
+        min_size = dynstr1->size;
+    else
+        min_size = dynstr2->size;
+    result = memcmp(dynstr1->mem, dynstr2->mem, min_size);
+    if (result == 0) {
+        if (dynstr1->size < dynstr2->size)
+            return -1;
+        else if (dynstr1->size == dynstr2->size)
+            return 0;
+        else
+            return 1;
+    }
+    return result;
+}
+
+
+size_t dynstr_fwrite(FILE *file, Dynstr *dynstr)
+{
+    return fwrite(dynstr->mem, 1, dynstr->size, file);
+}
+
+
+ssize_t dynstr_write(int fd, Dynstr *dynstr)
+{
+    return write(fd, dynstr->mem, dynstr->size);
+}
+
+
+/* A helper function for dynstr_read and dynstr_fread. The callback does
+ * the actual reading. */
+static Dynstr *read_helper(size_t (*callback)(FILE *f, int fd, unsigned char *buf,
+                                              size_t size),
+                           FILE *f, int fd, size_t size)
+{
+    Dynstr *dynstr;
+    Dynstr *dynstr2;
+    size_t n;
+    
+    dynstr = new_dynstr(NULL, size, true);
+    if (dynstr == NULL)
+        return NULL;
+
+    n = callback(f, fd, dynstr->mem, size);
+    if (n == DYNSTR_ERROR) {
+        dynstr_free(dynstr);
+        return NULL;
+    }
+    
+    if (n < size) {
+        dynstr2 = dynstr_substr(dynstr, 0, n);
+        if (dynstr2 == NULL) {
+            dynstr->size = n;
+        } else {
+            dynstr_free(dynstr);
+            dynstr = dynstr2;
+        }
+    }
+
+    return dynstr;
+}
+
+
+static size_t fread_callback(FILE *f, int fd, unsigned char *buf, size_t size)
+{
+    size_t n;
+    
+    n = fread(buf, 1, size, f);
+    if (n == 0 && ferror(f))
+        return DYNSTR_ERROR;
+    return n;
+}
+
+
+static size_t read_callback(FILE *f, int fd, unsigned char *buf, size_t size)
+{
+    ssize_t n;
+
+    do {
+        n = read(fd, buf, size);
+    } while (n == -1 && errno == EINTR);
+    if (n == -1)
+        return DYNSTR_ERROR;
+    return n;
+}
+
+
+Dynstr *dynstr_fread(FILE *file, size_t size)
+{
+    return read_helper(fread_callback, file, -1, size);
+}
+
+
+Dynstr *dynstr_read(int file, size_t size)
+{
+    return read_helper(read_callback, NULL, file, size);
+}
+
+
+/* Helper function for dynstr_readline and dynstr_freadline. The callback
+ * does the actual reading. Reading happens one byte at a time, since we
+ * must not read past the newline that terminates a line. */
+static Dynstr *readline_helper(int (*callback)(FILE *, int), FILE *f, int fd)
+{
+    Dynstr *line;
+    Dynstr *temp1;
+    Dynstr *temp2;
+    int c;
+    unsigned char buf[1024];
+    size_t buflen;
+    
+    line = dynstr_new_empty();
+    buflen = 0;
+
+    for (;;) {
+        temp1 = NULL;
+        temp2 = NULL;
+
+        c = callback(f, fd);
+        if (c == -1)
+            goto error;
+        else if (c == -2)
+            break;
+
+        buf[buflen++] = c;
+        if (buflen == sizeof(buf)) {
+            temp1 = dynstr_new_from_constant_memory(buf, buflen);
+            if (temp1 == NULL)
+                goto error;
+            temp2 = dynstr_cat(line, temp1);
+            if (temp2 == NULL)
+                goto error;
+            dynstr_free(temp1);
+            dynstr_free(line);
+            line = temp2;
+            buflen = 0;
+        }
+
+        if (c == '\n')
+            break;
+    }
+    
+    if (buflen > 0) {
+        temp1 = dynstr_new_from_constant_memory(buf, buflen);
+        if (temp1 == NULL)
+            goto error;
+        temp2 = dynstr_cat(line, temp1);
+        if (temp2 == NULL)
+            goto error;
+        dynstr_free(temp1);
+        dynstr_free(line);
+        line = temp2;
+    }
+
+    return line;
+
+error:
+    dynstr_free(line);
+    dynstr_free(temp1);
+    dynstr_free(temp2);
+    return NULL;
+}
+
+
+static int freadline_callback(FILE *f, int fd)
+{
+    int c;
+    
+    c = getc(f);
+    if (c == EOF && ferror(f))
+        return -1;
+    else if (c == EOF)
+        return -2;
+    else
+        return c;
+}
+
+
+Dynstr *dynstr_freadline(FILE *file)
+{
+    return readline_helper(freadline_callback, file, -1);
+}
+
+
+static int readline_callback(FILE *f, int fd)
+{
+    unsigned char c;
+    int n;
+
+    do {
+        n = read(fd, &c, 1);
+    } while (n == -1 && errno == EINTR);
+    if (n == 0)
+        return -2;
+    else if (n == -1)
+        return -1;
+    else
+        return c;
+}
+
+
+Dynstr *dynstr_readline(int file)
+{
+    return readline_helper(readline_callback, NULL, file);
+}
+
diff --git a/src/dynstr.h b/src/dynstr.h
new file mode 100644
index 0000000..302902d
--- /dev/null
+++ b/src/dynstr.h
@@ -0,0 +1,187 @@
+/*
+ * dynstr.h - dynamic C string library
+ *
+ * This is a library for managing dynamic C strings of bytes (not
+ * multibyte characters).
+ *
+ * Each dynamic string is immutable: once created, it cannot be modified.
+ * To achieve changes, create new strings. This allows an implementation
+ * of the API to make use of copy-on-write techniques to save memory,
+ * and avoid unnecessary copying.
+ *
+ * Dynamic allocation can fail. By default, the routines in this library
+ * return NULL for failures. The caller may use the 
+ * dynstr_set_malloc_error_handler function to set a function that gets
+ * called before NULL is returned. This function can, for example, abort
+ * the program (see dynstr_malloc_error_abort), or use longjmp to jump
+ * some error handling routine.
+ * 
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+#ifndef DYNSTR_H
+#define DYNSTR_H
+
+#include <stdarg.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stddef.h>
+
+
+/* Version number of the shared library. */
+#define DYNSTR_VERSION_MAJOR 0
+#define DYNSTR_VERSION_MINOR 0
+#define DYNSTR_VERSION_PATCH 0
+
+
+/* Magic value returned by functions that search for things within
+ * dynamic strings, to indicate 'not found'. */
+#define DYNSTR_NOT_FOUND (~(size_t)0)
+
+
+/* The abstract type for dynamic strings. The type is opaque: the caller
+ * may only operate on it using the functions declared in this header. */
+typedef struct Dynstr Dynstr;
+
+
+/* Initialize or re-initialize the library. This sets all global variables
+ * used internally to their defaults. This is mainly useful for unit
+ * tests. */
+void dynstr_init(void);
+
+/* Set the memory allocator to use, instead of malloc. This is mainly
+ * useful for unit tests. */
+void dynstr_set_malloc(void *(*allocator)(size_t));
+
+/* Get the memory allocator being used. This is mainly useful for unit 
+ * tests. */
+void *(*dynstr_get_malloc(void))(size_t);
+
+/* Type of callback functions for handling malloc failures. */
+typedef void dynstr_error_handler(int error, size_t size, void *oldptr);
+
+/* Get and set malloc error handler. */
+dynstr_error_handler *dynstr_get_malloc_error_handler(void);
+void dynstr_set_malloc_error_handler(dynstr_error_handler *handler);
+
+/* Malloc error handler that aborts the program (using abort, not exit). */
+void dynstr_malloc_error_abort(int error, size_t size, void *oldptr);
+
+/* Malloc error handler that does nothing. This is the default handler.
+ * It causes NULL to be returned. */
+void dynstr_malloc_error_indicate(int error, size_t size, void *oldptr);
+
+
+/* Create a new, empty string. */
+Dynstr *dynstr_new_empty(void);
+
+/* Create a new string, copy contents from a NUL-terminated C string. */
+Dynstr *dynstr_new_from_cstring(const char *cstring);
+
+/* Create a new string, copy contents from an arbitrary memory area. */
+Dynstr *dynstr_new_from_memory(const void *mem, size_t size);
+
+/* Create a new string, use contents from a constant C string. The caller
+ * MUST make sure the contents of the C string do not change while the
+ * dynamic string exists, since the dynamic string will not copy the
+ * contents, but use it directly. */
+Dynstr *dynstr_new_from_constant_cstring(const char *cstring);
+
+/* Create a new string, use contents from an arbitrary memory area. The caller
+ * MUST make sure the contents of the memory area do not change while the
+ * dynamic string exists, since the dynamic string will not copy the
+ * contents, but use it directly. */
+Dynstr *dynstr_new_from_constant_memory(const void *mem, size_t size);
+
+/* Free a dynamic string. */
+void dynstr_free(Dynstr *dynstr);
+
+/* Return length of dynamic string, in bytes. */
+size_t dynstr_len(Dynstr *dynstr);
+
+/* Is the dynamic string empty? In other words, is its length 0? */
+bool dynstr_is_empty(Dynstr *dynstr);
+
+/* Create a new string, copying its contents from an existing one. */
+Dynstr *dynstr_substr(Dynstr *dynstr, size_t offset, size_t size);
+
+/* Create a new string by catenating two existing ones. Return NULL on
+ * failure. */
+Dynstr *dynstr_cat(Dynstr *dynstr1, Dynstr *dynstr2);
+
+/* Create a new string by catenating zero or more existing ones. The
+ * argument list has zero or more pointers to dynamic strings, and
+ * then a NULL pointer. */
+Dynstr *dynstr_cat_many(Dynstr *dynstr, ...);
+
+/* Return value of byte at a given offset. The value is non-negative. If
+ * the offset is past the end of the string, -1 is returned. */
+int dynstr_byte_at(Dynstr *dynstr, size_t offset);
+
+/* Copy contents of a dynamic string into a memory area. If the offset or 
+ * size extends past the end of the string, only as much as actually exists 
+ * in the string is actually copied. The rest of the output memory area will 
+ * be filled with garbage. Return number of bytes actually copied, which may 
+ * be less than requested, and may be zero. */
+size_t dynstr_memcpy(void *mem, Dynstr *dynstr, size_t offset, size_t size);
+
+/* Create a dynamically allocated C string copy of the dynamic string.
+ * This is like strdup. If the dynamic string contains NUL bytes, then
+ * that is the caller's problem. Return pointer to the C string. The
+ * caller is responsible for freeing it. Return NULL on error. */
+char *dynstr_strdup(Dynstr *dynstr);
+
+/* Search for first or last byte with a given value in a string, 
+ * starting at a given offset and until the end of the string. Return offset 
+ * of matching byte, or DYNSTR_NOT_FOUND if not found. Offset is from 
+ * beginning of string. */
+size_t dynstr_first_byte(Dynstr *dynstr, size_t offset, int byte);
+size_t dynstr_last_byte(Dynstr *dynstr, size_t offset, int byte);
+
+/* Search for first or last occurrence of a substring in a string, 
+ * starting at a given offset and until the end of the string. Return 
+ * offset of match, or DYNSTR_NOT_FOUND if not found. Offset is from 
+ * beginning of string. */
+size_t dynstr_first_string(Dynstr *dynstr, size_t offset, Dynstr *pattern);
+size_t dynstr_last_string(Dynstr *dynstr, size_t offset, Dynstr *pattern);
+
+/* Compare two strings, return 0 if they are equal, negative if the
+ * first comes before the second, and positive if second comes first.
+ * Comparisons are done byte-by-byte using unsigned values. */
+int dynstr_cmp(Dynstr *dynstr1, Dynstr *dynstr2);
+
+/* Write a dynamic string into an open file (using stdio). Return value is 
+ * number of bytes written, just like for fwrite(3).
+ * If an error occurs, the size is less than the length of the string,
+ * and errno has been set by fwrite(3). */
+size_t dynstr_fwrite(FILE *file, Dynstr *dynstr);
+
+/* Write a dynamic string into an open Unix file handle. Return value is 
+ * number of bytes written, or -1. */
+ssize_t dynstr_write(int file, Dynstr *dynstr);
+
+/* Read a number of bytes from an open file, either FILE or a Unix file
+ * handle. Return value is the string that was read. The string is empty
+ * to indicate EOF, or NULL for error. */
+Dynstr *dynstr_fread(FILE *file, size_t size);
+Dynstr *dynstr_read(int file, size_t size);
+
+/* Read a line from an open file, either a FILE or a Unix file handle.
+ * The line ends with the first newline byte, or at the end of the file.
+ * If there was an error, NULL is returned, and errno is set, and the
+ * partially read line is discarded. */
+Dynstr *dynstr_freadline(FILE *file);
+Dynstr *dynstr_readline(int file);
+
+#endif
diff --git a/src/unittests.c b/src/unittests.c
new file mode 100644
index 0000000..0ba5b33
--- /dev/null
+++ b/src/unittests.c
@@ -0,0 +1,1287 @@
+/*
+ * unittests.c - unit tests for dynamic byte strings
+ * Copyright 2010  Lars Wirzenius
+ * 
+ * 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 <http://www.gnu.org/licenses/>.
+ */
+
+
+#define _GNU_SOURCE
+
+#include <setjmp.h>
+#include <signal.h>
+#include <stdbool.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <fcntl.h>
+
+#include "dynstr.h"
+
+
+#define FAIL(msg) \
+    do { \
+        printf("FAIL: %s\n", msg); \
+        return false; \
+    } while (0)
+
+
+#define FAIL_UNLESS(cond) \
+    do { \
+        if (!(cond)) { \
+            printf("FAIL: %s:%d: %s\n", \
+                __FUNCTION__, __LINE__, #cond); \
+            return false;\
+        } \
+    } while (0)
+
+
+#define FAIL_UNLESS_EQUAL(a,b) \
+    do { \
+        if ((a) != (b)) { \
+            printf("FAIL: %s:%d: not equal: '%s' and '%s'\n", \
+                __FUNCTION__, __LINE__, #a, #b); \
+            return false;\
+        } \
+    } while (0)
+
+
+#define MAX_STRINGS 128
+static Dynstr *strings[MAX_STRINGS];
+static int num_strings;
+
+static void add(Dynstr *dynstr)
+{
+    if (num_strings < MAX_STRINGS) {
+        strings[num_strings] = dynstr;
+        num_strings++;
+    }
+}
+
+static Dynstr *new_from_cstring(const char *cstring)
+{
+    Dynstr *dynstr;
+    
+    dynstr = dynstr_new_from_cstring(cstring);
+    add(dynstr);
+    return dynstr;
+}
+
+static Dynstr *substr(Dynstr *dynstr, size_t offset, size_t size)
+{
+    Dynstr *sub;
+    
+    sub = dynstr_substr(dynstr, offset, size);
+    add(sub);
+    return sub;
+}
+
+static void free_all_strings(void)
+{
+    while (num_strings > 0) {
+        num_strings--;
+        dynstr_free(strings[num_strings]);
+    }
+}
+
+
+static int test_default_error_handler_is_indicate(void)
+{
+    FAIL_UNLESS_EQUAL(dynstr_get_malloc_error_handler(),
+                      dynstr_malloc_error_indicate);
+    return true;
+}
+
+
+static int test_sets_error_handler(void)
+{
+    dynstr_set_malloc_error_handler(dynstr_malloc_error_abort);
+    FAIL_UNLESS_EQUAL(dynstr_get_malloc_error_handler(),
+                      dynstr_malloc_error_abort);
+    return true;
+}
+
+
+static int test_init_resets_error_handler(void)
+{
+    dynstr_set_malloc_error_handler(dynstr_malloc_error_abort);
+    dynstr_init();
+    FAIL_UNLESS_EQUAL(dynstr_get_malloc_error_handler(),
+                      dynstr_malloc_error_indicate);
+    return true;
+}
+
+
+static int test_indicate_handler_returns(void)
+{
+    dynstr_malloc_error_indicate(0, 0, NULL);
+    return true;
+}
+
+
+static jmp_buf env;
+static void abort_handler(int signo)
+{
+    longjmp(env, 1);
+}
+
+
+static int test_abort_handler_calls_abort(void)
+{
+    struct sigaction act;
+    struct sigaction oldact;
+    
+    if (setjmp(env) == 0) {
+        act.sa_handler = abort_handler;
+        sigemptyset(&act.sa_mask);
+        act.sa_flags = 0;
+        sigaction(SIGABRT, &act, &oldact);
+        dynstr_set_malloc_error_handler(dynstr_malloc_error_abort);
+        dynstr_malloc_error_abort(0, 0, 0);
+        FAIL("dynstr_malloc_error_abort returned");
+    } else {
+        sigaction(SIGABRT, &oldact, NULL);
+    }
+    return true;
+}
+
+
+static bool error_handler_called;
+
+static void error_handler(int error, size_t size, void *oldptr)
+{
+    error_handler_called = true;
+}
+
+static int fail_malloc_after;
+
+static void *fail_malloc(size_t size)
+{
+    if (fail_malloc_after <= 0)
+        return NULL;
+    --fail_malloc_after;
+    return malloc(size);
+}
+
+static int test_alloc_calls_error_handler(void)
+{
+    Dynstr *dynstr;
+    
+    error_handler_called = false;
+    dynstr_set_malloc_error_handler(error_handler);
+    dynstr_set_malloc(fail_malloc);
+    dynstr = dynstr_new_empty();
+    FAIL_UNLESS_EQUAL(dynstr, NULL);
+    FAIL_UNLESS_EQUAL(error_handler_called, true);
+    return true;
+}
+
+static int test_alloc_does_not_call_error_handler(void)
+{
+    Dynstr *dynstr;
+    
+    error_handler_called = false;
+    dynstr_set_malloc_error_handler(error_handler);
+    dynstr_set_malloc(malloc);
+    dynstr = dynstr_new_empty();
+    FAIL_UNLESS_EQUAL(error_handler_called, false);
+    dynstr_free(dynstr);
+    return true;
+}
+
+
+static int test_uses_malloc_by_default(void)
+{
+    dynstr_init();
+    FAIL_UNLESS_EQUAL(dynstr_get_malloc(), malloc);
+    return true;
+}
+
+
+static int test_sets_malloc(void)
+{
+    dynstr_set_malloc(fail_malloc);
+    FAIL_UNLESS_EQUAL(dynstr_get_malloc(), fail_malloc);
+    return true;
+}
+
+
+static int test_init_resets_malloc(void)
+{
+    dynstr_set_malloc(fail_malloc);
+    dynstr_init();
+    FAIL_UNLESS_EQUAL(dynstr_get_malloc(), malloc);
+    return true;
+}
+
+
+static int test_empty_string_is_empty(void)
+{
+    Dynstr *dynstr;
+    
+    dynstr = dynstr_new_empty();
+    FAIL_UNLESS_EQUAL(dynstr_len(dynstr), 0);
+    FAIL_UNLESS_EQUAL(dynstr_is_empty(dynstr), true);
+    dynstr_free(dynstr);
+    return true;
+}
+
+
+static int test_new_returns_NULL_upon_first_allocation_failure(void)
+{
+    Dynstr *dynstr;
+
+    dynstr_init();
+    dynstr_set_malloc(fail_malloc);    
+    dynstr = dynstr_new_empty();
+    FAIL_UNLESS_EQUAL(dynstr, NULL);
+    return true;
+}
+
+
+static int test_creates_from_cstring(void)
+{
+    const char bytes[] = "asdfasdfafdasdfasdfqw4tb";
+    char newbytes[sizeof(bytes)];
+    Dynstr *dynstr;
+    size_t size;
+    
+    dynstr = new_from_cstring(bytes);
+    FAIL_UNLESS_EQUAL(dynstr_len(dynstr), strlen(bytes));
+
+    size = dynstr_memcpy(newbytes, dynstr, 0, strlen(bytes));
+    FAIL_UNLESS_EQUAL(size, strlen(bytes));
+    FAIL_UNLESS_EQUAL(memcmp(bytes, newbytes, strlen(bytes)), 0);
+    
+    return true;
+}
+
+
+static int test_creates_from_memory(void)
+{
+    const char bytes[] = "asdfasdfafdasdfasdfqw4tb";
+    char newbytes[sizeof(bytes)];
+    Dynstr *dynstr;
+    size_t size;
+    
+    dynstr = dynstr_new_from_memory(bytes, sizeof(bytes));
+    FAIL_UNLESS_EQUAL(dynstr_len(dynstr), sizeof(bytes));
+
+    size = dynstr_memcpy(newbytes, dynstr, 0, sizeof(bytes));
+    FAIL_UNLESS_EQUAL(size, sizeof(bytes));
+    FAIL_UNLESS_EQUAL(memcmp(bytes, newbytes, sizeof(bytes)), 0);
+
+    dynstr_free(dynstr);
+    return true;
+}
+
+
+static int test_creates_from_constant_cstring(void)
+{
+    char bytes[] = "asdfasdfafdasdfasdfqw4tb";
+    char newbytes[sizeof(bytes)];
+    Dynstr *dynstr;
+    size_t size;
+    
+    dynstr = dynstr_new_from_constant_cstring(bytes);
+    FAIL_UNLESS_EQUAL(dynstr_len(dynstr), strlen(bytes));
+
+    size = dynstr_memcpy(newbytes, dynstr, 0, strlen(bytes));
+    FAIL_UNLESS_EQUAL(size, strlen(bytes));
+    FAIL_UNLESS_EQUAL(memcmp(bytes, newbytes, strlen(bytes)), 0);
+    
+    bytes[0] = 'x';
+    dynstr_memcpy(newbytes, dynstr, 0, strlen(bytes));
+    FAIL_UNLESS_EQUAL(memcmp(bytes, newbytes, strlen(bytes)), 0);
+    
+    dynstr_free(dynstr);
+    return true;
+}
+
+
+static int test_creates_from_constant_memory(void)
+{
+    char bytes[] = "asdfasdfafdasdfasdfqw4tb";
+    char newbytes[sizeof(bytes)];
+    Dynstr *dynstr;
+    size_t size;
+    
+    dynstr = dynstr_new_from_constant_memory(bytes, sizeof(bytes));
+    FAIL_UNLESS_EQUAL(dynstr_len(dynstr), sizeof(bytes));
+
+    size = dynstr_memcpy(newbytes, dynstr, 0, sizeof(bytes));
+    FAIL_UNLESS_EQUAL(size, sizeof(bytes));
+    FAIL_UNLESS_EQUAL(memcmp(bytes, newbytes, sizeof(bytes)), 0);
+
+    bytes[0] = 'x';
+    dynstr_memcpy(newbytes, dynstr, 0, sizeof(bytes));
+    FAIL_UNLESS_EQUAL(memcmp(bytes, newbytes, sizeof(bytes)), 0);
+
+    dynstr_free(dynstr);
+    return true;
+}
+
+
+static int test_memcpy_returns_zero_if_offset_is_too_large(void)
+{
+    Dynstr *dynstr;
+    char mem[1024];
+    
+    dynstr = new_from_cstring("hello");
+    FAIL_UNLESS_EQUAL(dynstr_memcpy(mem, dynstr, dynstr_len(dynstr), 1), 0);
+    FAIL_UNLESS_EQUAL(dynstr_memcpy(mem, dynstr, dynstr_len(dynstr) + 1, 1), 0);
+    return true;
+}
+
+
+static int test_memcpy_truncates_if_copying_too_much(void)
+{
+    Dynstr *dynstr;
+    char mem[1024];
+    size_t len;
+    
+    dynstr = new_from_cstring("hello");
+    len = dynstr_len(dynstr);
+    FAIL_UNLESS_EQUAL(dynstr_memcpy(mem, dynstr, 0, len), len);
+    FAIL_UNLESS_EQUAL(dynstr_memcpy(mem, dynstr, 0, len + 1), len);
+    return true;
+}
+
+
+static int test_memcpy_copies_whole_string_ok(void)
+{
+    Dynstr *dynstr;
+    const char data[] = "hello";
+    char mem[1024];
+    size_t len;
+    
+    dynstr = new_from_cstring(data);
+    len = dynstr_len(dynstr);
+    dynstr_memcpy(mem, dynstr, 0, len);
+    FAIL_UNLESS_EQUAL(memcmp(data, mem, len), 0);
+    return true;
+}
+
+
+static int test_memcpy_copies_substring_ok(void)
+{
+    Dynstr *dynstr;
+    const char data[] = "hello";
+    char mem[1024];
+    size_t len;
+    
+    dynstr = new_from_cstring(data);
+    len = dynstr_len(dynstr);
+    dynstr_memcpy(mem, dynstr, 1, len-2);
+    FAIL_UNLESS_EQUAL(memcmp(data + 1, mem, len-2), 0);
+    return true;
+}
+
+
+static int test_copies_empty_substring_ok(void)
+{
+    Dynstr *dynstr;
+    Dynstr *sub;
+    size_t size;
+    char buf[1024];
+    
+    dynstr = new_from_cstring("abcdef");
+    sub = substr(dynstr, 1, 0);
+    size = dynstr_memcpy(buf, sub, 0, dynstr_len(sub));
+    FAIL_UNLESS_EQUAL(size, 0);
+    return true;
+}
+
+
+static int test_copies_single_byte_substring_ok(void)
+{
+    Dynstr *dynstr;
+    Dynstr *sub;
+    size_t size;
+    char buf[1024];
+    
+    dynstr = new_from_cstring("abcdef");
+    sub = substr(dynstr, 1, 1);
+    size = dynstr_memcpy(buf, sub, 0, dynstr_len(sub));
+    FAIL_UNLESS_EQUAL(size, 1);
+    FAIL_UNLESS_EQUAL(memcmp(buf, "b", 1), 0);
+    return true;
+}
+
+
+static int test_copies_middle_substring_ok(void)
+{
+    Dynstr *dynstr;
+    Dynstr *sub;
+    size_t size;
+    char buf[1024];
+    
+    dynstr = new_from_cstring("abcdef");
+    sub = substr(dynstr, 1, 4);
+    size = dynstr_memcpy(buf, sub, 0, dynstr_len(sub));
+    FAIL_UNLESS_EQUAL(size, 4);
+    FAIL_UNLESS_EQUAL(memcmp(buf, "bcde", 4), 0);
+    return true;
+}
+
+
+static int test_copies_initial_substring_ok(void)
+{
+    Dynstr *dynstr;
+    Dynstr *sub;
+    size_t size;
+    char buf[1024];
+    
+    dynstr = new_from_cstring("abcdef");
+    sub = substr(dynstr, 0, 5);
+    size = dynstr_memcpy(buf, sub, 0, dynstr_len(sub));
+    FAIL_UNLESS_EQUAL(size, 5);
+    FAIL_UNLESS_EQUAL(memcmp(buf, "abcde", 5), 0);
+    return true;
+}
+
+
+static int test_copies_final_substring_ok(void)
+{
+    Dynstr *dynstr;
+    Dynstr *sub;
+    size_t size;
+    char buf[1024];
+    
+    dynstr = new_from_cstring("abcdef");
+    sub = substr(dynstr, 1, 5);
+    size = dynstr_memcpy(buf, sub, 0, dynstr_len(sub));
+    FAIL_UNLESS_EQUAL(size, 5);
+    FAIL_UNLESS_EQUAL(memcmp(buf, "bcdef", 5), 0);
+    return true;
+}
+
+
+static int test_copies_empty_substring_when_offset_too_big(void)
+{
+    Dynstr *dynstr;
+    Dynstr *sub;
+    size_t size;
+    char buf[1024];
+    
+    dynstr = new_from_cstring("abcdef");
+    sub = substr(dynstr, 100, 1);
+    size = dynstr_memcpy(buf, sub, 0, dynstr_len(sub));
+    FAIL_UNLESS_EQUAL(size, 0);
+    return true;
+}
+
+
+static int test_copies_partial_substring_when_length_too_big(void)
+{
+    Dynstr *dynstr;
+    Dynstr *sub;
+    size_t size;
+    char buf[1024];
+    
+    dynstr = new_from_cstring("abcdef");
+    sub = substr(dynstr, 1, 6);
+    size = dynstr_memcpy(buf, sub, 0, dynstr_len(sub));
+    FAIL_UNLESS_EQUAL(size, 5);
+    FAIL_UNLESS_EQUAL(memcmp(buf, "bcdef", 5), 0);
+    return true;
+}
+
+
+static int test_strdup_duplicates_string(void)
+{
+    Dynstr *dynstr;
+    char *cstring;
+    char data[] = "hello, world";
+    
+    dynstr = dynstr_new_from_constant_cstring(data);
+    cstring = dynstr_strdup(dynstr);
+    FAIL_UNLESS_EQUAL(memcmp(data, cstring, sizeof(data)), 0);
+    free(cstring);
+    dynstr_free(dynstr);
+    return true;
+}
+
+
+static int test_cats_ok(void)
+{
+    Dynstr *a;
+    Dynstr *b;
+    Dynstr *c;
+    char buf[1024];
+    size_t size;
+    
+    a = new_from_cstring("abc");
+    b = new_from_cstring("def");
+    c = dynstr_cat(a, b);
+    FAIL_UNLESS_EQUAL(dynstr_len(c), 6);
+    size = dynstr_memcpy(buf, c, 0, dynstr_len(c));
+    FAIL_UNLESS_EQUAL(size, 6);
+    FAIL_UNLESS_EQUAL(memcmp(buf, "abcdef", 6), 0);
+    dynstr_free(c);
+    return true;
+}
+
+
+static int test_cat_returns_NULL_for_first_malloc_failure(void)
+{
+    Dynstr *a;
+    Dynstr *b;
+    Dynstr *c;
+
+    a = new_from_cstring("abc");
+    b = new_from_cstring("def");
+    dynstr_set_malloc(fail_malloc);
+    c = dynstr_cat(a, b);
+    FAIL_UNLESS_EQUAL(c, NULL);
+    return true;
+}
+
+
+static int test_byteat_reports_correct_character(void)
+{
+    Dynstr *dynstr;
+    
+    dynstr = new_from_cstring("abc");
+    FAIL_UNLESS_EQUAL(dynstr_byte_at(dynstr, 1), 'b');
+    return true;
+}
+
+
+static int test_byteat_reports_error_for_too_large_offset(void)
+{
+    Dynstr *dynstr;
+    
+    dynstr = new_from_cstring("abc");
+    FAIL_UNLESS_EQUAL(dynstr_byte_at(dynstr, 1024), -1);
+    return true;
+}
+
+
+static int test_byteat_reports_0xff_correctly(void)
+{
+    Dynstr *dynstr;
+    
+    dynstr = new_from_cstring("\xff");
+    FAIL_UNLESS_EQUAL(dynstr_byte_at(dynstr, 0), 255);
+    return true;
+}
+
+
+static int test_first_byte_finds_byte(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    offset = dynstr_first_byte(dynstr, 0, '3');
+    FAIL_UNLESS_EQUAL(offset, 2);
+    return true;
+}
+
+
+static int test_first_byte_only_finds_first_byte(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    offset = dynstr_first_byte(dynstr, 0, '3');
+    FAIL_UNLESS_EQUAL(offset, 2);
+    return true;
+}
+
+
+static int test_first_byte_does_not_find_nonexistent_byte(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    offset = dynstr_first_byte(dynstr, 0, 'x');
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_first_byte_does_not_find_byte_outside_range(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    offset = dynstr_first_byte(dynstr, 4, '3');
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_first_byte_only_finds_byte_inside_range(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    offset = dynstr_first_byte(dynstr, 3, '3');
+    FAIL_UNLESS_EQUAL(offset, 5);
+    return true;
+}
+
+
+static int test_first_byte_does_not_find_in_range_outside_string(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    offset = dynstr_first_byte(dynstr, 128, '3');
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_last_byte_finds_byte(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    offset = dynstr_last_byte(dynstr, 0, '3');
+    FAIL_UNLESS_EQUAL(offset, 2);
+    return true;
+}
+
+
+static int test_last_byte_only_finds_last_byte(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    offset = dynstr_last_byte(dynstr, 0, '3');
+    FAIL_UNLESS_EQUAL(offset, 5);
+    return true;
+}
+
+
+static int test_last_byte_does_not_find_nonexistent_byte(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    offset = dynstr_last_byte(dynstr, 0, 'x');
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_last_byte_does_not_find_byte_outside_range(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    offset = dynstr_last_byte(dynstr, 4, '3');
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_last_byte_only_finds_byte_inside_range(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    offset = dynstr_last_byte(dynstr, 3, '3');
+    FAIL_UNLESS_EQUAL(offset, 5);
+    return true;
+}
+
+
+static int test_last_byte_does_not_find_in_range_outside_string(void)
+{
+    Dynstr *dynstr;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    offset = dynstr_last_byte(dynstr, 128, '3');
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_first_string_finds_pattern(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    pattern = new_from_cstring("345");
+    offset = dynstr_first_string(dynstr, 0, pattern);
+    FAIL_UNLESS_EQUAL(offset, 2);
+    return true;
+}
+
+
+static int test_first_string_only_finds_first_pattern(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    pattern = new_from_cstring("123");
+    offset = dynstr_first_string(dynstr, 0, pattern);
+    FAIL_UNLESS_EQUAL(offset, 0);
+    return true;
+}
+
+
+static int test_first_string_does_not_find_nonexistent_pattern(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    pattern = new_from_cstring("x");
+    offset = dynstr_first_string(dynstr, 0, pattern);
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_first_string_does_not_find_pattern_outside_range(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    pattern = new_from_cstring("123");
+    offset = dynstr_first_string(dynstr, 3, pattern);
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_first_string_only_finds_pattern_inside_range(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    pattern = new_from_cstring("3");
+    offset = dynstr_first_string(dynstr, 3, pattern);
+    FAIL_UNLESS_EQUAL(offset, 5);
+    return true;
+}
+
+
+static int test_first_string_does_not_find_empty_pattern(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    pattern = new_from_cstring("");
+    offset = dynstr_first_string(dynstr, 0, pattern);
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_last_string_finds_pattern(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    pattern = new_from_cstring("345");
+    offset = dynstr_last_string(dynstr, 0, pattern);
+    FAIL_UNLESS_EQUAL(offset, 2);
+    return true;
+}
+
+
+static int test_last_string_only_finds_last_pattern(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    pattern = new_from_cstring("123");
+    offset = dynstr_last_string(dynstr, 0, pattern);
+    FAIL_UNLESS_EQUAL(offset, 3);
+    return true;
+}
+
+
+static int test_last_string_does_not_find_nonexistent_pattern(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    pattern = new_from_cstring("x");
+    offset = dynstr_last_string(dynstr, 0, pattern);
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_last_string_does_not_find_pattern_outside_range(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123456");
+    pattern = new_from_cstring("123");
+    offset = dynstr_last_string(dynstr, 3, pattern);
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+
+static int test_last_string_only_finds_pattern_inside_range(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    pattern = new_from_cstring("3");
+    offset = dynstr_last_string(dynstr, 3, pattern);
+    FAIL_UNLESS_EQUAL(offset, 5);
+    return true;
+}
+
+
+static int test_last_string_does_not_find_empty_pattern(void)
+{
+    Dynstr *dynstr;
+    Dynstr *pattern;
+    size_t offset;
+    
+    dynstr = new_from_cstring("123123");
+    pattern = new_from_cstring("");
+    offset = dynstr_last_string(dynstr, 0, pattern);
+    FAIL_UNLESS_EQUAL(offset, DYNSTR_NOT_FOUND);
+    return true;
+}
+
+static int test_cmp_returns_0_for_equal_strings(void)
+{
+    Dynstr *a;
+    Dynstr *b;
+    
+    a = new_from_cstring("foo");
+    b = new_from_cstring("foo");
+    FAIL_UNLESS_EQUAL(dynstr_cmp(a, b), 0);
+    return true;
+}
+
+
+static int test_cmp_returns_0_for_empty_strings(void)
+{
+    Dynstr *a;
+    Dynstr *b;
+    
+    a = dynstr_new_empty();
+    b = dynstr_new_empty();
+    FAIL_UNLESS_EQUAL(dynstr_cmp(a, b), 0);
+    dynstr_free(a);
+    dynstr_free(b);
+    return true;
+}
+
+
+static int test_cmp_returns_negative_if_only_first_string_is_empty(void)
+{
+    Dynstr *a;
+    Dynstr *b;
+    
+    a = new_from_cstring("");
+    b = new_from_cstring("foo");
+    FAIL_UNLESS(dynstr_cmp(a, b) < 0);
+    return true;
+}
+
+
+static int test_cmp_returns_positive_if_only_second_string_is_empty(void)
+{
+    Dynstr *a;
+    Dynstr *b;
+    
+    a = new_from_cstring("foo");
+    b = new_from_cstring("");
+    FAIL_UNLESS(dynstr_cmp(a, b) > 0);
+    return true;
+}
+
+
+static int test_cmp_returns_negative_if_first_string_comes_first(void)
+{
+    Dynstr *a;
+    Dynstr *b;
+    
+    a = new_from_cstring("x");
+    b = new_from_cstring("\xff"); /* Check for unsigned comparision, too. */
+    FAIL_UNLESS(dynstr_cmp(a, b) < 0);
+    return true;
+}
+
+
+static int test_cmp_returns_positive_if_second_string_comes_first(void)
+{
+    Dynstr *a;
+    Dynstr *b;
+    
+    a = new_from_cstring("\xff");
+    b = new_from_cstring("x");
+    FAIL_UNLESS(dynstr_cmp(a, b) > 0);
+    return true;
+}
+
+
+static int write_test(long (*callback)(char *filename, Dynstr *dynstr))
+{
+    char tempname[] = "unittest.tmp.XXXXXX";
+    int fd;
+    size_t num_bytes;
+    Dynstr *dynstr;
+    Dynstr *dynstr2;
+    char buf[1024];
+    int read_bytes;
+    
+    dynstr = new_from_cstring("life is too short for str* and mem* in apps");
+    
+    fd = mkstemp(tempname);
+    if (fd == -1)
+        abort();
+
+    num_bytes = callback(tempname, dynstr);
+
+    FAIL_UNLESS_EQUAL(num_bytes, dynstr_len(dynstr));
+    
+    read_bytes = read(fd, buf, sizeof(buf));
+    if (read_bytes == -1)
+        abort();
+    close(fd);
+    remove(tempname);
+
+    dynstr2 = dynstr_new_from_memory(buf, read_bytes);
+    FAIL_UNLESS_EQUAL(read_bytes, dynstr_len(dynstr));
+    FAIL_UNLESS_EQUAL(dynstr_cmp(dynstr, dynstr2), 0);
+    dynstr_free(dynstr2);
+
+    return true;
+}
+
+
+static long fwrite_callback(char *filename, Dynstr *dynstr)
+{
+    FILE *f;
+    long num_bytes;
+    
+    f = fopen(filename, "w");
+    num_bytes = dynstr_fwrite(f, dynstr);
+    fclose(f);
+    return num_bytes;
+}
+
+
+static int test_fwrite_writes_string(void)
+{
+    return write_test(fwrite_callback);
+}
+
+
+static long write_callback(char *filename, Dynstr *dynstr)
+{
+    int fd;
+    long num_bytes;
+    
+    fd = open(filename, O_WRONLY, 0);
+    num_bytes = dynstr_write(fd, dynstr);
+    close(fd);
+    return num_bytes;
+}
+
+
+static int test_write_writes_string(void)
+{
+    return write_test(write_callback);
+}
+
+
+static int read_test(Dynstr *(*callback)(char *filename, size_t size))
+{
+    char tempname[] = "unittest.tmp.XXXXXX";
+    int fd;
+    Dynstr *dynstr;
+    Dynstr *dynstr2;
+    const char canonical[] = "life is too short for str* and mem* in apps";
+    
+    fd = mkstemp(tempname);
+    if (fd == -1)
+        abort();
+    if (write(fd, canonical, sizeof(canonical)) == -1)
+        abort();
+    close(fd);
+
+    dynstr = callback(tempname, sizeof(canonical) * 2);
+    remove(tempname);
+
+    FAIL_UNLESS(dynstr != NULL);
+    FAIL_UNLESS_EQUAL(dynstr_len(dynstr), sizeof(canonical));
+    
+    dynstr2 = dynstr_new_from_memory(canonical, sizeof(canonical));
+    FAIL_UNLESS_EQUAL(dynstr_cmp(dynstr, dynstr2), 0);
+
+    dynstr_free(dynstr);
+    dynstr_free(dynstr2);
+
+    return true;
+}
+
+
+static Dynstr *fread_callback(char *filename, size_t size)
+{
+    FILE *f;
+    Dynstr *dynstr;
+    
+    f = fopen(filename, "r");
+    dynstr = dynstr_fread(f, size);
+    fclose(f);
+    return dynstr;
+}
+
+
+static int test_fread_reads_string(void)
+{
+    return read_test(fread_callback);
+}
+
+
+static Dynstr *read_callback(char *filename, size_t size)
+{
+    int fd;
+    Dynstr *dynstr;
+    
+    fd = open(filename, O_RDONLY, 0);
+    dynstr = dynstr_read(fd, size);
+    close(fd);
+    return dynstr;
+}
+
+
+static int test_read_reads_string(void)
+{
+    return read_test(read_callback);
+}
+
+
+static int readline_test(Dynstr *(*callback)(char *filename))
+{
+    char tempname[] = "unittest.tmp.XXXXXX";
+    int fd;
+    const char cline1[] = "life is too short for str* and mem* in apps\n";
+    const char cline2[] = "use dynstr instead!\n";
+    Dynstr *lines;
+    Dynstr *line1;
+    Dynstr *line2;
+    Dynstr *result;
+    
+    fd = mkstemp(tempname);
+    if (fd == -1)
+        abort();
+        
+    line1 = dynstr_new_from_constant_cstring(cline1);
+    line2 = dynstr_new_from_constant_cstring(cline2);
+    lines = dynstr_cat(line1, line2);
+    if (dynstr_write(fd, lines) != dynstr_len(lines))
+        abort();
+    close(fd);
+    
+    result = callback(tempname);
+    remove(tempname);
+
+    FAIL_UNLESS_EQUAL(dynstr_cmp(line1, result), 0);
+
+    dynstr_free(line1);
+    dynstr_free(line2);
+    dynstr_free(lines);
+    dynstr_free(result);
+
+    return true;
+}
+
+
+static Dynstr *freadline_callback(char *filename)
+{
+    FILE *f;
+    Dynstr *line1;
+    
+    f = fopen(filename, "r");
+    line1 = dynstr_freadline(f);
+    fclose(f);
+    return line1;
+}
+
+
+static int test_freadline_reads_first_line(void)
+{
+    return readline_test(freadline_callback);
+}
+
+
+static Dynstr *readline_callback(char *filename)
+{
+    int fd;
+    Dynstr *line1;
+    
+    fd = open(filename, O_RDONLY, 0);
+    line1 = dynstr_readline(fd);
+    close(fd);
+    return line1;
+}
+
+
+static int test_readline_reads_first_line(void)
+{
+    return readline_test(readline_callback);
+}
+
+
+static void setup(void)
+{
+    dynstr_init();
+    fail_malloc_after = 0;
+}
+
+
+static void teardown(void)
+{
+    free_all_strings();
+}
+
+
+struct test {
+    const char *name;
+    int (*test)(void);
+};
+
+
+#define TEST(func) { #func, func }
+
+static const struct test tests[] = {
+    TEST(test_default_error_handler_is_indicate),
+    TEST(test_sets_error_handler),
+    TEST(test_init_resets_error_handler),
+    TEST(test_uses_malloc_by_default),
+    TEST(test_sets_malloc),
+    TEST(test_init_resets_malloc),
+    TEST(test_alloc_calls_error_handler),
+    TEST(test_alloc_does_not_call_error_handler),
+    TEST(test_indicate_handler_returns),
+    TEST(test_abort_handler_calls_abort),
+    TEST(test_empty_string_is_empty),
+    TEST(test_new_returns_NULL_upon_first_allocation_failure),
+    TEST(test_creates_from_cstring),
+    TEST(test_creates_from_memory),
+    TEST(test_creates_from_constant_cstring),
+    TEST(test_creates_from_constant_memory),
+    TEST(test_memcpy_returns_zero_if_offset_is_too_large),
+    TEST(test_memcpy_truncates_if_copying_too_much),
+    TEST(test_memcpy_copies_whole_string_ok),
+    TEST(test_memcpy_copies_substring_ok),
+    TEST(test_strdup_duplicates_string),
+    TEST(test_copies_empty_substring_ok),
+    TEST(test_copies_single_byte_substring_ok),
+    TEST(test_copies_middle_substring_ok),
+    TEST(test_copies_initial_substring_ok),
+    TEST(test_copies_final_substring_ok),
+    TEST(test_copies_empty_substring_when_offset_too_big),
+    TEST(test_copies_partial_substring_when_length_too_big),
+    TEST(test_cats_ok),
+    TEST(test_cat_returns_NULL_for_first_malloc_failure),
+    TEST(test_byteat_reports_correct_character),
+    TEST(test_byteat_reports_error_for_too_large_offset),
+    TEST(test_byteat_reports_0xff_correctly),
+    TEST(test_first_byte_finds_byte),
+    TEST(test_first_byte_only_finds_first_byte),
+    TEST(test_first_byte_does_not_find_nonexistent_byte),
+    TEST(test_first_byte_does_not_find_byte_outside_range),
+    TEST(test_first_byte_only_finds_byte_inside_range),
+    TEST(test_first_byte_does_not_find_in_range_outside_string),
+    TEST(test_last_byte_finds_byte),
+    TEST(test_last_byte_only_finds_last_byte),
+    TEST(test_last_byte_does_not_find_nonexistent_byte),
+    TEST(test_last_byte_does_not_find_byte_outside_range),
+    TEST(test_last_byte_only_finds_byte_inside_range),
+    TEST(test_last_byte_does_not_find_in_range_outside_string),
+    TEST(test_first_string_finds_pattern),
+    TEST(test_first_string_only_finds_first_pattern),
+    TEST(test_first_string_does_not_find_nonexistent_pattern),
+    TEST(test_first_string_does_not_find_pattern_outside_range),
+    TEST(test_first_string_only_finds_pattern_inside_range),
+    TEST(test_first_string_does_not_find_empty_pattern),
+    TEST(test_last_string_finds_pattern),
+    TEST(test_last_string_only_finds_last_pattern),
+    TEST(test_last_string_does_not_find_nonexistent_pattern),
+    TEST(test_last_string_does_not_find_pattern_outside_range),
+    TEST(test_last_string_only_finds_pattern_inside_range),
+    TEST(test_last_string_does_not_find_empty_pattern),
+    TEST(test_cmp_returns_0_for_equal_strings),
+    TEST(test_cmp_returns_0_for_empty_strings),
+    TEST(test_cmp_returns_negative_if_only_first_string_is_empty),
+    TEST(test_cmp_returns_positive_if_only_second_string_is_empty),
+    TEST(test_cmp_returns_negative_if_first_string_comes_first),
+    TEST(test_cmp_returns_positive_if_second_string_comes_first),
+    TEST(test_fwrite_writes_string),
+    TEST(test_write_writes_string),
+    TEST(test_fread_reads_string),
+    TEST(test_read_reads_string),
+    TEST(test_freadline_reads_first_line),
+    TEST(test_readline_reads_first_line),
+};
+static const int num_tests = sizeof(tests) / sizeof(tests[0]);
+
+int main(void)
+{
+    int exit;
+
+    exit = EXIT_SUCCESS;
+    for (int i = 0; i < num_tests; ++i) {
+        setup();
+        if (!tests[i].test()) {
+            exit = EXIT_FAILURE;
+        }
+        teardown();
+    }
+    return exit;
+}