real_path_internal(): add comment explaining use of cwd

diff --git a/trace.c b/trace.c
index 35d388dce44a4a8e3d6053dfd6abcb652771818a..5ec0e3bd16b5cfc59254c6e10d4555ef3029aa36 100644 (file)
--- a/trace.c
+++ b/trace.c
@@ -25,10 +25,10 @@
 #include "cache.h"
 #include "quote.h"
 
-/* Get a trace file descriptor from GIT_TRACE env variable. */
-static int get_trace_fd(int *need_close)
+/* Get a trace file descriptor from "key" env variable. */
+static int get_trace_fd(const char *key, int *need_close)
 {
-       char *trace = getenv("GIT_TRACE");
+       char *trace = getenv(key);
 
        if (!trace || !strcmp(trace, "") ||
            !strcmp(trace, "0") || !strcasecmp(trace, "false"))
@@ -50,10 +50,10 @@ static int get_trace_fd(int *need_close)
                return fd;
        }
 
-       fprintf(stderr, "What does '%s' for GIT_TRACE mean?\n", trace);
+       fprintf(stderr, "What does '%s' for %s mean?\n", trace, key);
        fprintf(stderr, "If you want to trace into a file, "
-               "then please set GIT_TRACE to an absolute pathname "
-               "(starting with /).\n");
+               "then please set %s to an absolute pathname "
+               "(starting with /).\n", key);
        fprintf(stderr, "Defaulting to tracing on stderr...\n");
 
        return STDERR_FILENO;
@@ -62,33 +62,44 @@ static int get_trace_fd(int *need_close)
 static const char err_msg[] = "Could not trace into fd given by "
        "GIT_TRACE environment variable";
 
-void trace_printf(const char *fmt, ...)
+static void trace_vprintf(const char *key, const char *fmt, va_list ap)
 {
-       struct strbuf buf;
-       va_list ap;
-       int fd, len, need_close = 0;
+       struct strbuf buf = STRBUF_INIT;
 
-       fd = get_trace_fd(&need_close);
-       if (!fd)
+       if (!trace_want(key))
                return;
 
        set_try_to_free_routine(NULL);  /* is never reset */
-       strbuf_init(&buf, 64);
+       strbuf_vaddf(&buf, fmt, ap);
+       trace_strbuf(key, &buf);
+       strbuf_release(&buf);
+}
+
+static void trace_printf_key(const char *key, const char *fmt, ...)
+{
+       va_list ap;
        va_start(ap, fmt);
-       len = vsnprintf(buf.buf, strbuf_avail(&buf), fmt, ap);
+       trace_vprintf(key, fmt, ap);
        va_end(ap);
-       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);
+void trace_printf(const char *fmt, ...)
+{
+       va_list ap;
+       va_start(ap, fmt);
+       trace_vprintf("GIT_TRACE", fmt, ap);
+       va_end(ap);
+}
+
+void trace_strbuf(const char *key, const struct strbuf *buf)
+{
+       int fd, need_close = 0;
+
+       fd = get_trace_fd(key, &need_close);
+       if (!fd)
+               return;
+
+       write_or_whine_pipe(fd, buf->buf, buf->len, err_msg);
 
        if (need_close)
                close(fd);
@@ -96,28 +107,18 @@ void trace_printf(const char *fmt, ...)
 
 void trace_argv_printf(const char **argv, const char *fmt, ...)
 {
-       struct strbuf buf;
+       struct strbuf buf = STRBUF_INIT;
        va_list ap;
-       int fd, len, need_close = 0;
+       int fd, need_close = 0;
 
-       fd = get_trace_fd(&need_close);
+       fd = get_trace_fd("GIT_TRACE", &need_close);
        if (!fd)
                return;
 
        set_try_to_free_routine(NULL);  /* is never reset */
-       strbuf_init(&buf, 64);
        va_start(ap, fmt);
-       len = vsnprintf(buf.buf, strbuf_avail(&buf), fmt, ap);
+       strbuf_vaddf(&buf, fmt, ap);
        va_end(ap);
-       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);
 
        sq_quote_argv(&buf, argv, 0);
        strbuf_addch(&buf, '\n');
@@ -154,12 +155,11 @@ static const char *quote_crnl(const char *path)
 /* FIXME: move prefix to startup_info struct and get rid of this arg */
 void trace_repo_setup(const char *prefix)
 {
+       static const char *key = "GIT_TRACE_SETUP";
        const char *git_work_tree;
        char cwd[PATH_MAX];
-       char *trace = getenv("GIT_TRACE");
 
-       if (!trace || !strcmp(trace, "") ||
-           !strcmp(trace, "0") || !strcasecmp(trace, "false"))
+       if (!trace_want(key))
                return;
 
        if (!getcwd(cwd, PATH_MAX))
@@ -171,8 +171,18 @@ void trace_repo_setup(const char *prefix)
        if (!prefix)
                prefix = "(null)";
 
-       trace_printf("setup: git_dir: %s\n", quote_crnl(get_git_dir()));
-       trace_printf("setup: worktree: %s\n", quote_crnl(git_work_tree));
-       trace_printf("setup: cwd: %s\n", quote_crnl(cwd));
-       trace_printf("setup: prefix: %s\n", quote_crnl(prefix));
+       trace_printf_key(key, "setup: git_dir: %s\n", quote_crnl(get_git_dir()));
+       trace_printf_key(key, "setup: worktree: %s\n", quote_crnl(git_work_tree));
+       trace_printf_key(key, "setup: cwd: %s\n", quote_crnl(cwd));
+       trace_printf_key(key, "setup: prefix: %s\n", quote_crnl(prefix));
+}
+
+int trace_want(const char *key)
+{
+       const char *trace = getenv(key);
+
+       if (!trace || !strcmp(trace, "") ||
+           !strcmp(trace, "0") || !strcasecmp(trace, "false"))
+               return 0;
+       return 1;
 }