sq_quote_argv and add_to_string rework with strbuf's.

* sq_quote_buf is made public, and works on a strbuf.
* sq_quote_argv also works on a strbuf.
* make sq_quote_argv take a "maxlen" argument to check the buffer won't grow
  too big.

Signed-off-by: Pierre Habouzit <madcoder@debian.org>
Signed-off-by: Junio C Hamano <gitster@pobox.com>

diff --git a/connect.c b/connect.c
index 1653a0e..06d279e 100644 (file)
--- a/connect.c
+++ b/connect.c
@@ -577,16 +577,13 @@ pid_t git_connect(int fd[2], char *url, const char *prog, int flags)
        if (pid < 0)
                die("unable to fork");
        if (!pid) {
-               char command[MAX_CMD_LEN];
-               char *posn = command;
-               int size = MAX_CMD_LEN;
-               int of = 0;
+               struct strbuf cmd;
 
-               of |= add_to_string(&posn, &size, prog, 0);
-               of |= add_to_string(&posn, &size, " ", 0);
-               of |= add_to_string(&posn, &size, path, 1);
-
-               if (of)
+               strbuf_init(&cmd, MAX_CMD_LEN);
+               strbuf_addstr(&cmd, prog);
+               strbuf_addch(&cmd, ' ');
+               sq_quote_buf(&cmd, path);
+               if (cmd.len >= MAX_CMD_LEN)
                        die("command line too long");
 
                dup2(pipefd[1][0], 0);
@@ -606,10 +603,10 @@ pid_t git_connect(int fd[2], char *url, const char *prog, int flags)
                                ssh_basename++;
 
                        if (!port)
-                               execlp(ssh, ssh_basename, host, command, NULL);
+                               execlp(ssh, ssh_basename, host, cmd.buf, NULL);
                        else
                                execlp(ssh, ssh_basename, "-p", port, host,
-                                      command, NULL);
+                                      cmd.buf, NULL);
                }
                else {
                        unsetenv(ALTERNATE_DB_ENVIRONMENT);
@@ -618,7 +615,7 @@ pid_t git_connect(int fd[2], char *url, const char *prog, int flags)
                        unsetenv(GIT_WORK_TREE_ENVIRONMENT);
                        unsetenv(GRAFT_ENVIRONMENT);
                        unsetenv(INDEX_ENVIRONMENT);
-                       execlp("sh", "sh", "-c", command, NULL);
+                       execlp("sh", "sh", "-c", cmd.buf, NULL);
                }
                die("exec failed");
        }

diff --git a/git.c b/git.c
index 56ae8cc..9eaca1d 100644 (file)
--- a/git.c
+++ b/git.c
@@ -187,19 +187,13 @@ static int handle_alias(int *argcp, const char ***argv)
        if (alias_string) {
                if (alias_string[0] == '!') {
                        if (*argcp > 1) {
-                               int i, sz = PATH_MAX;
-                               char *s = xmalloc(sz), *new_alias = s;
+                               struct strbuf buf;
 
-                               add_to_string(&s, &sz, alias_string, 0);
+                               strbuf_init(&buf, PATH_MAX);
+                               strbuf_addstr(&buf, alias_string);
+                               sq_quote_argv(&buf, (*argv) + 1, *argcp - 1, PATH_MAX);
                                free(alias_string);
-                               alias_string = new_alias;
-                               for (i = 1; i < *argcp &&
-                                       !add_to_string(&s, &sz, " ", 0) &&
-                                       !add_to_string(&s, &sz, (*argv)[i], 1)
-                                       ; i++)
-                                       ; /* do nothing */
-                               if (!sz)
-                                       die("Too many or long arguments");
+                               alias_string = buf.buf;
                        }
                        trace_printf("trace: alias to shell cmd: %s => %s\n",
                                     alias_command, alias_string + 1);

diff --git a/quote.c b/quote.c
index b1efe18..800fd88 100644 (file)
--- a/quote.c
+++ b/quote.c
@@ -12,37 +12,31 @@
  *  a'b      ==> a'\''b    ==> 'a'\''b'
  *  a!b      ==> a'\!'b    ==> 'a'\!'b'
  */
-#undef EMIT
-#define EMIT(x) do { if (++len < n) *bp++ = (x); } while(0)
-
 static inline int need_bs_quote(char c)
 {
        return (c == '\'' || c == '!');
 }
 
-static size_t sq_quote_buf(char *dst, size_t n, const char *src)
+void sq_quote_buf(struct strbuf *dst, const char *src)
 {
-       char c;
-       char *bp = dst;
-       size_t len = 0;
-
-       EMIT('\'');
-       while ((c = *src++)) {
-               if (need_bs_quote(c)) {
-                       EMIT('\'');
-                       EMIT('\\');
-                       EMIT(c);
-                       EMIT('\'');
-               } else {
-                       EMIT(c);
+       char *to_free = NULL;
+
+       if (dst->buf == src)
+               to_free = strbuf_detach(dst);
+
+       strbuf_addch(dst, '\'');
+       while (*src) {
+               size_t len = strcspn(src, "'\\");
+               strbuf_add(dst, src, len);
+               src += len;
+               while (need_bs_quote(*src)) {
+                       strbuf_addstr(dst, "'\\");
+                       strbuf_addch(dst, *src++);
+                       strbuf_addch(dst, '\'');
                }
        }
-       EMIT('\'');
-
-       if ( n )
-               *bp = 0;
-
-       return len;
+       strbuf_addch(dst, '\'');
+       free(to_free);
 }
 
 void sq_quote_print(FILE *stream, const char *src)
@@ -62,11 +56,10 @@ void sq_quote_print(FILE *stream, const char *src)
        fputc('\'', stream);
 }
 
-char *sq_quote_argv(const char** argv, int count)
+void sq_quote_argv(struct strbuf *dst, const char** argv, int count,
+                   size_t maxlen)
 {
-       char *buf, *to;
        int i;
-       size_t len = 0;
 
        /* Count argv if needed. */
        if (count < 0) {
@@ -74,53 +67,14 @@ char *sq_quote_argv(const char** argv, int count)
                        ; /* just counting */
        }
 
-       /* Special case: no argv. */
-       if (!count)
-               return xcalloc(1,1);
-
-       /* Get destination buffer length. */
-       for (i = 0; i < count; i++)
-               len += sq_quote_buf(NULL, 0, argv[i]) + 1;
-
-       /* Alloc destination buffer. */
-       to = buf = xmalloc(len + 1);
-
        /* Copy into destination buffer. */
+       strbuf_grow(dst, 32 * count);
        for (i = 0; i < count; ++i) {
-               *to++ = ' ';
-               to += sq_quote_buf(to, len, argv[i]);
+               strbuf_addch(dst, ' ');
+               sq_quote_buf(dst, argv[i]);
+               if (maxlen && dst->len > maxlen)
+                       die("Too many or long arguments");
        }
-
-       return buf;
-}
-
-/*
- * Append a string to a string buffer, with or without shell quoting.
- * Return true if the buffer overflowed.
- */
-int add_to_string(char **ptrp, int *sizep, const char *str, int quote)
-{
-       char *p = *ptrp;
-       int size = *sizep;
-       int oc;
-       int err = 0;
-
-       if (quote)
-               oc = sq_quote_buf(p, size, str);
-       else {
-               oc = strlen(str);
-               memcpy(p, str, (size <= oc) ? size - 1 : oc);
-       }
-
-       if (size <= oc) {
-               err = 1;
-               oc = size - 1;
-       }
-
-       *ptrp += oc;
-       **ptrp = '\0';
-       *sizep -= oc;
-       return err;
 }
 
 char *sq_dequote(char *arg)

diff --git a/quote.h b/quote.h
index 2769f71..4287990 100644 (file)
--- a/quote.h
+++ b/quote.h
@@ -29,13 +29,10 @@
  */
 
 extern void sq_quote_print(FILE *stream, const char *src);
-extern char *sq_quote_argv(const char** argv, int count);
 
-/*
- * Append a string to a string buffer, with or without shell quoting.
- * Return true if the buffer overflowed.
- */
-extern int add_to_string(char **ptrp, int *sizep, const char *str, int quote);
+extern void sq_quote_buf(struct strbuf *, const char *src);
+extern void sq_quote_argv(struct strbuf *, const char **argv, int count,
+                          size_t maxlen);
 
 /* This unwraps what sq_quote() produces in place, but returns
  * NULL if the input does not look like what sq_quote would have

diff --git a/rsh.c b/rsh.c
index 5754a23..016d72e 100644 (file)
--- a/rsh.c
+++ b/rsh.c
@@ -10,12 +10,9 @@ int setup_connection(int *fd_in, int *fd_out, const char *remote_prog,
        char *host;
        char *path;
        int sv[2];
-       char command[COMMAND_SIZE];
-       char *posn;
-       int sizen;
-       int of;
        int i;
        pid_t pid;
+       struct strbuf cmd;
 
        if (!strcmp(url, "-")) {
                *fd_in = 0;
@@ -36,24 +33,23 @@ int setup_connection(int *fd_in, int *fd_out, const char *remote_prog,
        if (!path) {
                return error("Bad URL: %s", url);
        }
+
        /* $GIT_RSH <host> "env GIT_DIR=<path> <remote_prog> <args...>" */
-       sizen = COMMAND_SIZE;
-       posn = command;
-       of = 0;
-       of |= add_to_string(&posn, &sizen, "env ", 0);
-       of |= add_to_string(&posn, &sizen, GIT_DIR_ENVIRONMENT "=", 0);
-       of |= add_to_string(&posn, &sizen, path, 1);
-       of |= add_to_string(&posn, &sizen, " ", 0);
-       of |= add_to_string(&posn, &sizen, remote_prog, 1);
+       strbuf_init(&cmd, COMMAND_SIZE);
+       strbuf_addstr(&cmd, "env ");
+       strbuf_addstr(&cmd, GIT_DIR_ENVIRONMENT "=");
+       sq_quote_buf(&cmd, path);
+       strbuf_addch(&cmd, ' ');
+       sq_quote_buf(&cmd, remote_prog);
 
-       for ( i = 0 ; i < rmt_argc ; i++ ) {
-               of |= add_to_string(&posn, &sizen, " ", 0);
-               of |= add_to_string(&posn, &sizen, rmt_argv[i], 1);
+       for (i = 0 ; i < rmt_argc ; i++) {
+               strbuf_addch(&cmd, ' ');
+               sq_quote_buf(&cmd, rmt_argv[i]);
        }
 
-       of |= add_to_string(&posn, &sizen, " -", 0);
+       strbuf_addstr(&cmd, " -");
 
-       if ( of )
+       if (cmd.len >= COMMAND_SIZE)
                return error("Command line too long");
 
        if (socketpair(AF_UNIX, SOCK_STREAM, 0, sv))
@@ -74,7 +70,7 @@ int setup_connection(int *fd_in, int *fd_out, const char *remote_prog,
                close(sv[1]);
                dup2(sv[0], 0);
                dup2(sv[0], 1);
-               execlp(ssh, ssh_basename, host, command, NULL);
+               execlp(ssh, ssh_basename, host, cmd.buf, NULL);
        }
        close(sv[0]);
        *fd_in = sv[1];

diff --git a/trace.c b/trace.c
index 91548a5..69fa05e 100644 (file)
--- a/trace.c
+++ b/trace.c
@@ -64,7 +64,7 @@ static const char err_msg[] = "Could not trace into fd given by "
 
 void trace_printf(const char *fmt, ...)
 {
-       char buf[8192];
+       struct strbuf buf;
        va_list ap;
        int fd, len, need_close = 0;
 
@@ -72,12 +72,22 @@ void trace_printf(const char *fmt, ...)
        if (!fd)
                return;
 
+       strbuf_init(&buf, 0);
        va_start(ap, fmt);
-       len = vsnprintf(buf, sizeof(buf), fmt, ap);
+       len = vsnprintf(buf.buf, strbuf_avail(&buf), fmt, ap);
        va_end(ap);
-       if (len >= sizeof(buf))
-               die("unreasonnable trace length");
-       write_or_whine_pipe(fd, buf, len, err_msg);
+       if (len >= strbuf_avail(&buf)) {
+               strbuf_grow(&buf, len - strbuf_avail(&buf) + 128);
+               va_start(ap, fmt);
+               len = vsnprintf(buf.buf, strbuf_avail(&buf), fmt, ap);
+               va_end(ap);
+               if (len >= strbuf_avail(&buf))
+                       die("broken vsnprintf");
+       }
+       strbuf_setlen(&buf, len);
+
+       write_or_whine_pipe(fd, buf.buf, buf.len, err_msg);
+       strbuf_release(&buf);
 
        if (need_close)
                close(fd);
@@ -85,31 +95,32 @@ void trace_printf(const char *fmt, ...)
 
 void trace_argv_printf(const char **argv, int count, const char *fmt, ...)
 {
-       char buf[8192];
+       struct strbuf buf;
        va_list ap;
-       char *argv_str;
-       size_t argv_len;
        int fd, len, need_close = 0;
 
        fd = get_trace_fd(&need_close);
        if (!fd)
                return;
 
+       strbuf_init(&buf, 0);
        va_start(ap, fmt);
-       len = vsnprintf(buf, sizeof(buf), fmt, ap);
+       len = vsnprintf(buf.buf, strbuf_avail(&buf), fmt, ap);
        va_end(ap);
-       if (len >= sizeof(buf))
-               die("unreasonnable trace length");
-
-       /* Get the argv string. */
-       argv_str = sq_quote_argv(argv, count);
-       argv_len = strlen(argv_str);
-
-       write_or_whine_pipe(fd, buf, len, err_msg);
-       write_or_whine_pipe(fd, argv_str, argv_len, err_msg);
-       write_or_whine_pipe(fd, "\n", 1, err_msg);
+       if (len >= strbuf_avail(&buf)) {
+               strbuf_grow(&buf, len - strbuf_avail(&buf) + 128);
+               va_start(ap, fmt);
+               len = vsnprintf(buf.buf, strbuf_avail(&buf), fmt, ap);
+               va_end(ap);
+               if (len >= strbuf_avail(&buf))
+                       die("broken vsnprintf");
+       }
+       strbuf_setlen(&buf, len);
 
-       free(argv_str);
+       sq_quote_argv(&buf, argv, count, 0);
+       strbuf_addch(&buf, '\n');
+       write_or_whine_pipe(fd, buf.buf, buf.len, err_msg);
+       strbuf_release(&buf);
 
        if (need_close)
                close(fd);