-#include <stdio.h>
-#include <stdlib.h>
-#include "strbuf.h"
#include "cache.h"
+#include "refs.h"
+#include "utf8.h"
-void strbuf_init(struct strbuf *sb) {
- sb->buf = 0;
- sb->eof = sb->alloc = sb->len = 0;
+int starts_with(const char *str, const char *prefix)
+{
+ for (; ; str++, prefix++)
+ if (!*prefix)
+ return 1;
+ else if (*str != *prefix)
+ return 0;
}
-static void strbuf_begin(struct strbuf *sb) {
- free(sb->buf);
- strbuf_init(sb);
+/*
+ * Used as the default ->buf value, so that people can always assume
+ * buf is non NULL and ->buf is NUL terminated even for a freshly
+ * initialized strbuf.
+ */
+char strbuf_slopbuf[1];
+
+void strbuf_init(struct strbuf *sb, size_t hint)
+{
+ sb->alloc = sb->len = 0;
+ sb->buf = strbuf_slopbuf;
+ if (hint)
+ strbuf_grow(sb, hint);
+}
+
+void strbuf_release(struct strbuf *sb)
+{
+ if (sb->alloc) {
+ free(sb->buf);
+ strbuf_init(sb, 0);
+ }
+}
+
+char *strbuf_detach(struct strbuf *sb, size_t *sz)
+{
+ char *res;
+ strbuf_grow(sb, 0);
+ res = sb->buf;
+ if (sz)
+ *sz = sb->len;
+ strbuf_init(sb, 0);
+ return res;
+}
+
+void strbuf_attach(struct strbuf *sb, void *buf, size_t len, size_t alloc)
+{
+ strbuf_release(sb);
+ sb->buf = buf;
+ sb->len = len;
+ sb->alloc = alloc;
+ strbuf_grow(sb, 0);
+ sb->buf[sb->len] = '\0';
+}
+
+void strbuf_grow(struct strbuf *sb, size_t extra)
+{
+ int new_buf = !sb->alloc;
+ if (unsigned_add_overflows(extra, 1) ||
+ unsigned_add_overflows(sb->len, extra + 1))
+ die("you want to use way too much memory");
+ if (new_buf)
+ sb->buf = NULL;
+ ALLOC_GROW(sb->buf, sb->len + extra + 1, sb->alloc);
+ if (new_buf)
+ sb->buf[0] = '\0';
+}
+
+void strbuf_trim(struct strbuf *sb)
+{
+ strbuf_rtrim(sb);
+ strbuf_ltrim(sb);
+}
+void strbuf_rtrim(struct strbuf *sb)
+{
+ while (sb->len > 0 && isspace((unsigned char)sb->buf[sb->len - 1]))
+ sb->len--;
+ sb->buf[sb->len] = '\0';
+}
+
+void strbuf_ltrim(struct strbuf *sb)
+{
+ char *b = sb->buf;
+ while (sb->len > 0 && isspace(*b)) {
+ b++;
+ sb->len--;
+ }
+ memmove(sb->buf, b, sb->len);
+ sb->buf[sb->len] = '\0';
+}
+
+int strbuf_reencode(struct strbuf *sb, const char *from, const char *to)
+{
+ char *out;
+ int len;
+
+ if (same_encoding(from, to))
+ return 0;
+
+ out = reencode_string_len(sb->buf, sb->len, to, from, &len);
+ if (!out)
+ return -1;
+
+ strbuf_attach(sb, out, len, len);
+ return 0;
+}
+
+void strbuf_tolower(struct strbuf *sb)
+{
+ char *p = sb->buf, *end = sb->buf + sb->len;
+ for (; p < end; p++)
+ *p = tolower(*p);
+}
+
+struct strbuf **strbuf_split_buf(const char *str, size_t slen,
+ int terminator, int max)
+{
+ struct strbuf **ret = NULL;
+ size_t nr = 0, alloc = 0;
+ struct strbuf *t;
+
+ while (slen) {
+ int len = slen;
+ if (max <= 0 || nr + 1 < max) {
+ const char *end = memchr(str, terminator, slen);
+ if (end)
+ len = end - str + 1;
+ }
+ t = xmalloc(sizeof(struct strbuf));
+ strbuf_init(t, len);
+ strbuf_add(t, str, len);
+ ALLOC_GROW(ret, nr + 2, alloc);
+ ret[nr++] = t;
+ str += len;
+ slen -= len;
+ }
+ ALLOC_GROW(ret, nr + 1, alloc); /* In case string was empty */
+ ret[nr] = NULL;
+ return ret;
+}
+
+void strbuf_list_free(struct strbuf **sbs)
+{
+ struct strbuf **s = sbs;
+
+ while (*s) {
+ strbuf_release(*s);
+ free(*s++);
+ }
+ free(sbs);
+}
+
+int strbuf_cmp(const struct strbuf *a, const struct strbuf *b)
+{
+ int len = a->len < b->len ? a->len: b->len;
+ int cmp = memcmp(a->buf, b->buf, len);
+ if (cmp)
+ return cmp;
+ return a->len < b->len ? -1: a->len != b->len;
+}
+
+void strbuf_splice(struct strbuf *sb, size_t pos, size_t len,
+ const void *data, size_t dlen)
+{
+ if (unsigned_add_overflows(pos, len))
+ die("you want to use way too much memory");
+ if (pos > sb->len)
+ die("`pos' is too far after the end of the buffer");
+ if (pos + len > sb->len)
+ die("`pos + len' is too far after the end of the buffer");
+
+ if (dlen >= len)
+ strbuf_grow(sb, dlen - len);
+ memmove(sb->buf + pos + dlen,
+ sb->buf + pos + len,
+ sb->len - pos - len);
+ memcpy(sb->buf + pos, data, dlen);
+ strbuf_setlen(sb, sb->len + dlen - len);
+}
+
+void strbuf_insert(struct strbuf *sb, size_t pos, const void *data, size_t len)
+{
+ strbuf_splice(sb, pos, 0, data, len);
+}
+
+void strbuf_remove(struct strbuf *sb, size_t pos, size_t len)
+{
+ strbuf_splice(sb, pos, len, NULL, 0);
+}
+
+void strbuf_add(struct strbuf *sb, const void *data, size_t len)
+{
+ strbuf_grow(sb, len);
+ memcpy(sb->buf + sb->len, data, len);
+ strbuf_setlen(sb, sb->len + len);
+}
+
+void strbuf_adddup(struct strbuf *sb, size_t pos, size_t len)
+{
+ strbuf_grow(sb, len);
+ memcpy(sb->buf + sb->len, sb->buf + pos, len);
+ strbuf_setlen(sb, sb->len + len);
+}
+
+void strbuf_addchars(struct strbuf *sb, int c, size_t n)
+{
+ strbuf_grow(sb, n);
+ memset(sb->buf + sb->len, c, n);
+ strbuf_setlen(sb, sb->len + n);
+}
+
+void strbuf_addf(struct strbuf *sb, const char *fmt, ...)
+{
+ va_list ap;
+ va_start(ap, fmt);
+ strbuf_vaddf(sb, fmt, ap);
+ va_end(ap);
}
-static void inline strbuf_add(struct strbuf *sb, int ch) {
- if (sb->alloc <= sb->len) {
- sb->alloc = sb->alloc * 3 / 2 + 16;
- sb->buf = xrealloc(sb->buf, sb->alloc);
+static void add_lines(struct strbuf *out,
+ const char *prefix1,
+ const char *prefix2,
+ const char *buf, size_t size)
+{
+ while (size) {
+ const char *prefix;
+ const char *next = memchr(buf, '\n', size);
+ next = next ? (next + 1) : (buf + size);
+
+ prefix = ((prefix2 && (buf[0] == '\n' || buf[0] == '\t'))
+ ? prefix2 : prefix1);
+ strbuf_addstr(out, prefix);
+ strbuf_add(out, buf, next - buf);
+ size -= next - buf;
+ buf = next;
+ }
+ strbuf_complete_line(out);
+}
+
+void strbuf_add_commented_lines(struct strbuf *out, const char *buf, size_t size)
+{
+ static char prefix1[3];
+ static char prefix2[2];
+
+ if (prefix1[0] != comment_line_char) {
+ xsnprintf(prefix1, sizeof(prefix1), "%c ", comment_line_char);
+ xsnprintf(prefix2, sizeof(prefix2), "%c", comment_line_char);
+ }
+ add_lines(out, prefix1, prefix2, buf, size);
+}
+
+void strbuf_commented_addf(struct strbuf *sb, const char *fmt, ...)
+{
+ va_list params;
+ struct strbuf buf = STRBUF_INIT;
+ int incomplete_line = sb->len && sb->buf[sb->len - 1] != '\n';
+
+ va_start(params, fmt);
+ strbuf_vaddf(&buf, fmt, params);
+ va_end(params);
+
+ strbuf_add_commented_lines(sb, buf.buf, buf.len);
+ if (incomplete_line)
+ sb->buf[--sb->len] = '\0';
+
+ strbuf_release(&buf);
+}
+
+void strbuf_vaddf(struct strbuf *sb, const char *fmt, va_list ap)
+{
+ int len;
+ va_list cp;
+
+ if (!strbuf_avail(sb))
+ strbuf_grow(sb, 64);
+ va_copy(cp, ap);
+ len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, cp);
+ va_end(cp);
+ if (len < 0)
+ die("BUG: your vsnprintf is broken (returned %d)", len);
+ if (len > strbuf_avail(sb)) {
+ strbuf_grow(sb, len);
+ len = vsnprintf(sb->buf + sb->len, sb->alloc - sb->len, fmt, ap);
+ if (len > strbuf_avail(sb))
+ die("BUG: your vsnprintf is broken (insatiable)");
+ }
+ strbuf_setlen(sb, sb->len + len);
+}
+
+void strbuf_expand(struct strbuf *sb, const char *format, expand_fn_t fn,
+ void *context)
+{
+ for (;;) {
+ const char *percent;
+ size_t consumed;
+
+ percent = strchrnul(format, '%');
+ strbuf_add(sb, format, percent - format);
+ if (!*percent)
+ break;
+ format = percent + 1;
+
+ if (*format == '%') {
+ strbuf_addch(sb, '%');
+ format++;
+ continue;
+ }
+
+ consumed = fn(sb, format, context);
+ if (consumed)
+ format += consumed;
+ else
+ strbuf_addch(sb, '%');
+ }
+}
+
+size_t strbuf_expand_dict_cb(struct strbuf *sb, const char *placeholder,
+ void *context)
+{
+ struct strbuf_expand_dict_entry *e = context;
+ size_t len;
+
+ for (; e->placeholder && (len = strlen(e->placeholder)); e++) {
+ if (!strncmp(placeholder, e->placeholder, len)) {
+ if (e->value)
+ strbuf_addstr(sb, e->value);
+ return len;
+ }
+ }
+ return 0;
+}
+
+void strbuf_addbuf_percentquote(struct strbuf *dst, const struct strbuf *src)
+{
+ int i, len = src->len;
+
+ for (i = 0; i < len; i++) {
+ if (src->buf[i] == '%')
+ strbuf_addch(dst, '%');
+ strbuf_addch(dst, src->buf[i]);
+ }
+}
+
+size_t strbuf_fread(struct strbuf *sb, size_t size, FILE *f)
+{
+ size_t res;
+ size_t oldalloc = sb->alloc;
+
+ strbuf_grow(sb, size);
+ res = fread(sb->buf + sb->len, 1, size, f);
+ if (res > 0)
+ strbuf_setlen(sb, sb->len + res);
+ else if (oldalloc == 0)
+ strbuf_release(sb);
+ return res;
+}
+
+ssize_t strbuf_read(struct strbuf *sb, int fd, size_t hint)
+{
+ size_t oldlen = sb->len;
+ size_t oldalloc = sb->alloc;
+
+ strbuf_grow(sb, hint ? hint : 8192);
+ for (;;) {
+ ssize_t want = sb->alloc - sb->len - 1;
+ ssize_t got = read_in_full(fd, sb->buf + sb->len, want);
+
+ if (got < 0) {
+ if (oldalloc == 0)
+ strbuf_release(sb);
+ else
+ strbuf_setlen(sb, oldlen);
+ return -1;
+ }
+ sb->len += got;
+ if (got < want)
+ break;
+ strbuf_grow(sb, 8192);
+ }
+
+ sb->buf[sb->len] = '\0';
+ return sb->len - oldlen;
+}
+
+ssize_t strbuf_read_once(struct strbuf *sb, int fd, size_t hint)
+{
+ ssize_t cnt;
+
+ strbuf_grow(sb, hint ? hint : 8192);
+ cnt = xread(fd, sb->buf + sb->len, sb->alloc - sb->len - 1);
+ if (cnt > 0)
+ strbuf_setlen(sb, sb->len + cnt);
+ return cnt;
+}
+
+#define STRBUF_MAXLINK (2*PATH_MAX)
+
+int strbuf_readlink(struct strbuf *sb, const char *path, size_t hint)
+{
+ size_t oldalloc = sb->alloc;
+
+ if (hint < 32)
+ hint = 32;
+
+ while (hint < STRBUF_MAXLINK) {
+ int len;
+
+ strbuf_grow(sb, hint);
+ len = readlink(path, sb->buf, hint);
+ if (len < 0) {
+ if (errno != ERANGE)
+ break;
+ } else if (len < hint) {
+ strbuf_setlen(sb, len);
+ return 0;
+ }
+
+ /* .. the buffer was too small - try again */
+ hint *= 2;
}
- sb->buf[sb->len++] = ch;
+ if (oldalloc == 0)
+ strbuf_release(sb);
+ return -1;
}
-static void strbuf_end(struct strbuf *sb) {
- strbuf_add(sb, 0);
+int strbuf_getcwd(struct strbuf *sb)
+{
+ size_t oldalloc = sb->alloc;
+ size_t guessed_len = 128;
+
+ for (;; guessed_len *= 2) {
+ strbuf_grow(sb, guessed_len);
+ if (getcwd(sb->buf, sb->alloc)) {
+ strbuf_setlen(sb, strlen(sb->buf));
+ return 0;
+ }
+ if (errno != ERANGE)
+ break;
+ }
+ if (oldalloc == 0)
+ strbuf_release(sb);
+ else
+ strbuf_reset(sb);
+ return -1;
}
-void read_line(struct strbuf *sb, FILE *fp, int term) {
+#ifdef HAVE_GETDELIM
+int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
+{
+ ssize_t r;
+
+ if (feof(fp))
+ return EOF;
+
+ strbuf_reset(sb);
+
+ /* Translate slopbuf to NULL, as we cannot call realloc on it */
+ if (!sb->alloc)
+ sb->buf = NULL;
+ r = getdelim(&sb->buf, &sb->alloc, term, fp);
+
+ if (r > 0) {
+ sb->len = r;
+ return 0;
+ }
+ assert(r == -1);
+
+ /*
+ * Normally we would have called xrealloc, which will try to free
+ * memory and recover. But we have no way to tell getdelim() to do so.
+ * Worse, we cannot try to recover ENOMEM ourselves, because we have
+ * no idea how many bytes were read by getdelim.
+ *
+ * Dying here is reasonable. It mirrors what xrealloc would do on
+ * catastrophic memory failure. We skip the opportunity to free pack
+ * memory and retry, but that's unlikely to help for a malloc small
+ * enough to hold a single line of input, anyway.
+ */
+ if (errno == ENOMEM)
+ die("Out of memory, getdelim failed");
+
+ /* Restore slopbuf that we moved out of the way before */
+ if (!sb->buf)
+ strbuf_init(sb, 0);
+ return EOF;
+}
+#else
+int strbuf_getwholeline(struct strbuf *sb, FILE *fp, int term)
+{
int ch;
- strbuf_begin(sb);
- if (feof(fp)) {
- sb->eof = 1;
- return;
+
+ if (feof(fp))
+ return EOF;
+
+ strbuf_reset(sb);
+ flockfile(fp);
+ while ((ch = getc_unlocked(fp)) != EOF) {
+ if (!strbuf_avail(sb))
+ strbuf_grow(sb, 1);
+ sb->buf[sb->len++] = ch;
+ if (ch == term)
+ break;
+ }
+ funlockfile(fp);
+ if (ch == EOF && sb->len == 0)
+ return EOF;
+
+ sb->buf[sb->len] = '\0';
+ return 0;
+}
+#endif
+
+static int strbuf_getdelim(struct strbuf *sb, FILE *fp, int term)
+{
+ if (strbuf_getwholeline(sb, fp, term))
+ return EOF;
+ if (sb->buf[sb->len - 1] == term)
+ strbuf_setlen(sb, sb->len - 1);
+ return 0;
+}
+
+int strbuf_getline(struct strbuf *sb, FILE *fp)
+{
+ if (strbuf_getwholeline(sb, fp, '\n'))
+ return EOF;
+ if (sb->buf[sb->len - 1] == '\n') {
+ strbuf_setlen(sb, sb->len - 1);
+ if (sb->len && sb->buf[sb->len - 1] == '\r')
+ strbuf_setlen(sb, sb->len - 1);
}
- while ((ch = fgetc(fp)) != EOF) {
+ return 0;
+}
+
+int strbuf_getline_lf(struct strbuf *sb, FILE *fp)
+{
+ return strbuf_getdelim(sb, fp, '\n');
+}
+
+int strbuf_getline_nul(struct strbuf *sb, FILE *fp)
+{
+ return strbuf_getdelim(sb, fp, '\0');
+}
+
+int strbuf_getwholeline_fd(struct strbuf *sb, int fd, int term)
+{
+ strbuf_reset(sb);
+
+ while (1) {
+ char ch;
+ ssize_t len = xread(fd, &ch, 1);
+ if (len <= 0)
+ return EOF;
+ strbuf_addch(sb, ch);
if (ch == term)
break;
- strbuf_add(sb, ch);
}
- strbuf_end(sb);
+ return 0;
+}
+
+ssize_t strbuf_read_file(struct strbuf *sb, const char *path, size_t hint)
+{
+ int fd;
+ ssize_t len;
+
+ fd = open(path, O_RDONLY);
+ if (fd < 0)
+ return -1;
+ len = strbuf_read(sb, fd, hint);
+ close(fd);
+ if (len < 0)
+ return -1;
+
+ return len;
+}
+
+void strbuf_add_lines(struct strbuf *out, const char *prefix,
+ const char *buf, size_t size)
+{
+ add_lines(out, prefix, NULL, buf, size);
+}
+
+void strbuf_addstr_xml_quoted(struct strbuf *buf, const char *s)
+{
+ while (*s) {
+ size_t len = strcspn(s, "\"<>&");
+ strbuf_add(buf, s, len);
+ s += len;
+ switch (*s) {
+ case '"':
+ strbuf_addstr(buf, """);
+ break;
+ case '<':
+ strbuf_addstr(buf, "<");
+ break;
+ case '>':
+ strbuf_addstr(buf, ">");
+ break;
+ case '&':
+ strbuf_addstr(buf, "&");
+ break;
+ case 0:
+ return;
+ }
+ s++;
+ }
+}
+
+static int is_rfc3986_reserved(char ch)
+{
+ switch (ch) {
+ case '!': case '*': case '\'': case '(': case ')': case ';':
+ case ':': case '@': case '&': case '=': case '+': case '$':
+ case ',': case '/': case '?': case '#': case '[': case ']':
+ return 1;
+ }
+ return 0;
}
+static int is_rfc3986_unreserved(char ch)
+{
+ return isalnum(ch) ||
+ ch == '-' || ch == '_' || ch == '.' || ch == '~';
+}
+
+static void strbuf_add_urlencode(struct strbuf *sb, const char *s, size_t len,
+ int reserved)
+{
+ strbuf_grow(sb, len);
+ while (len--) {
+ char ch = *s++;
+ if (is_rfc3986_unreserved(ch) ||
+ (!reserved && is_rfc3986_reserved(ch)))
+ strbuf_addch(sb, ch);
+ else
+ strbuf_addf(sb, "%%%02x", ch);
+ }
+}
+
+void strbuf_addstr_urlencode(struct strbuf *sb, const char *s,
+ int reserved)
+{
+ strbuf_add_urlencode(sb, s, strlen(s), reserved);
+}
+
+void strbuf_humanise_bytes(struct strbuf *buf, off_t bytes)
+{
+ if (bytes > 1 << 30) {
+ strbuf_addf(buf, "%u.%2.2u GiB",
+ (int)(bytes >> 30),
+ (int)(bytes & ((1 << 30) - 1)) / 10737419);
+ } else if (bytes > 1 << 20) {
+ int x = bytes + 5243; /* for rounding */
+ strbuf_addf(buf, "%u.%2.2u MiB",
+ x >> 20, ((x & ((1 << 20) - 1)) * 100) >> 20);
+ } else if (bytes > 1 << 10) {
+ int x = bytes + 5; /* for rounding */
+ strbuf_addf(buf, "%u.%2.2u KiB",
+ x >> 10, ((x & ((1 << 10) - 1)) * 100) >> 10);
+ } else {
+ strbuf_addf(buf, "%u bytes", (int)bytes);
+ }
+}
+
+void strbuf_add_absolute_path(struct strbuf *sb, const char *path)
+{
+ if (!*path)
+ die("The empty string is not a valid path");
+ if (!is_absolute_path(path)) {
+ struct stat cwd_stat, pwd_stat;
+ size_t orig_len = sb->len;
+ char *cwd = xgetcwd();
+ char *pwd = getenv("PWD");
+ if (pwd && strcmp(pwd, cwd) &&
+ !stat(cwd, &cwd_stat) &&
+ (cwd_stat.st_dev || cwd_stat.st_ino) &&
+ !stat(pwd, &pwd_stat) &&
+ pwd_stat.st_dev == cwd_stat.st_dev &&
+ pwd_stat.st_ino == cwd_stat.st_ino)
+ strbuf_addstr(sb, pwd);
+ else
+ strbuf_addstr(sb, cwd);
+ if (sb->len > orig_len && !is_dir_sep(sb->buf[sb->len - 1]))
+ strbuf_addch(sb, '/');
+ free(cwd);
+ }
+ strbuf_addstr(sb, path);
+}
+
+int printf_ln(const char *fmt, ...)
+{
+ int ret;
+ va_list ap;
+ va_start(ap, fmt);
+ ret = vprintf(fmt, ap);
+ va_end(ap);
+ if (ret < 0 || putchar('\n') == EOF)
+ return -1;
+ return ret + 1;
+}
+
+int fprintf_ln(FILE *fp, const char *fmt, ...)
+{
+ int ret;
+ va_list ap;
+ va_start(ap, fmt);
+ ret = vfprintf(fp, fmt, ap);
+ va_end(ap);
+ if (ret < 0 || putc('\n', fp) == EOF)
+ return -1;
+ return ret + 1;
+}
+
+char *xstrdup_tolower(const char *string)
+{
+ char *result;
+ size_t len, i;
+
+ len = strlen(string);
+ result = xmallocz(len);
+ for (i = 0; i < len; i++)
+ result[i] = tolower(string[i]);
+ result[i] = '\0';
+ return result;
+}
+
+char *xstrvfmt(const char *fmt, va_list ap)
+{
+ struct strbuf buf = STRBUF_INIT;
+ strbuf_vaddf(&buf, fmt, ap);
+ return strbuf_detach(&buf, NULL);
+}
+
+char *xstrfmt(const char *fmt, ...)
+{
+ va_list ap;
+ char *ret;
+
+ va_start(ap, fmt);
+ ret = xstrvfmt(fmt, ap);
+ va_end(ap);
+
+ return ret;
+}
+
+void strbuf_addftime(struct strbuf *sb, const char *fmt, const struct tm *tm)
+{
+ size_t hint = 128;
+ size_t len;
+
+ if (!*fmt)
+ return;
+
+ strbuf_grow(sb, hint);
+ len = strftime(sb->buf + sb->len, sb->alloc - sb->len, fmt, tm);
+
+ if (!len) {
+ /*
+ * strftime reports "0" if it could not fit the result in the buffer.
+ * Unfortunately, it also reports "0" if the requested time string
+ * takes 0 bytes. So our strategy is to munge the format so that the
+ * output contains at least one character, and then drop the extra
+ * character before returning.
+ */
+ struct strbuf munged_fmt = STRBUF_INIT;
+ strbuf_addf(&munged_fmt, "%s ", fmt);
+ while (!len) {
+ hint *= 2;
+ strbuf_grow(sb, hint);
+ len = strftime(sb->buf + sb->len, sb->alloc - sb->len,
+ munged_fmt.buf, tm);
+ }
+ strbuf_release(&munged_fmt);
+ len--; /* drop munged space */
+ }
+ strbuf_setlen(sb, sb->len + len);
+}
+
+void strbuf_add_unique_abbrev(struct strbuf *sb, const unsigned char *sha1,
+ int abbrev_len)
+{
+ int r;
+ strbuf_grow(sb, GIT_SHA1_HEXSZ + 1);
+ r = find_unique_abbrev_r(sb->buf + sb->len, sha1, abbrev_len);
+ strbuf_setlen(sb, sb->len + r);
+}
+
+/*
+ * Returns the length of a line, without trailing spaces.
+ *
+ * If the line ends with newline, it will be removed too.
+ */
+static size_t cleanup(char *line, size_t len)
+{
+ while (len) {
+ unsigned char c = line[len - 1];
+ if (!isspace(c))
+ break;
+ len--;
+ }
+
+ return len;
+}
+
+/*
+ * Remove empty lines from the beginning and end
+ * and also trailing spaces from every line.
+ *
+ * Turn multiple consecutive empty lines between paragraphs
+ * into just one empty line.
+ *
+ * If the input has only empty lines and spaces,
+ * no output will be produced.
+ *
+ * If last line does not have a newline at the end, one is added.
+ *
+ * Enable skip_comments to skip every line starting with comment
+ * character.
+ */
+void strbuf_stripspace(struct strbuf *sb, int skip_comments)
+{
+ int empties = 0;
+ size_t i, j, len, newlen;
+ char *eol;
+
+ /* We may have to add a newline. */
+ strbuf_grow(sb, 1);
+
+ for (i = j = 0; i < sb->len; i += len, j += newlen) {
+ eol = memchr(sb->buf + i, '\n', sb->len - i);
+ len = eol ? eol - (sb->buf + i) + 1 : sb->len - i;
+
+ if (skip_comments && len && sb->buf[i] == comment_line_char) {
+ newlen = 0;
+ continue;
+ }
+ newlen = cleanup(sb->buf + i, len);
+
+ /* Not just an empty line? */
+ if (newlen) {
+ if (empties > 0 && j > 0)
+ sb->buf[j++] = '\n';
+ empties = 0;
+ memmove(sb->buf + j, sb->buf + i, newlen);
+ sb->buf[newlen + j++] = '\n';
+ } else {
+ empties++;
+ }
+ }
+
+ strbuf_setlen(sb, j);
+}