str: introduce `git_str` for internal, `git_buf` is externalethomson/gitstr

libgit2 has two distinct requirements that were previously solved by
`git_buf`.  We require:

1. A general purpose string class that provides a number of utility APIs
   for manipulating data (eg, concatenating, truncating, etc).
2. A structure that we can use to return strings to callers that they
   can take ownership of.

By using a single class (`git_buf`) for both of these purposes, we have
confused the API to the point that refactorings are difficult and
reasoning about correctness is also difficult.

Move the utility class `git_buf` to be called `git_str`: this represents
its general purpose, as an internal string buffer class.  The name also
is an homage to Junio Hamano ("gitstr").

The public API remains `git_buf`, and has a much smaller footprint.  It
is generally only used as an "out" param with strict requirements that
follow the documentation.  (Exceptions exist for some legacy APIs to
avoid breaking callers unnecessarily.)

Utility functions exist to convert a user-specified `git_buf` to a
`git_str` so that we can call internal functions, then converting it
back again.

1 files changed, 64 insertions, 64 deletions

diff --git a/src/net.c b/src/net.c
index 361e40e7b..58792ee7d 100644
--- a/src/net.c
+++ b/src/net.c
@@ -12,7 +12,7 @@
 #include "git2/errors.h"
 
 #include "posix.h"
-#include "buffer.h"
+#include "str.h"
 #include "http_parser.h"
 #include "runtime.h"
 
@@ -79,13 +79,13 @@ int git_net_url_parse(git_net_url *url, const char *given)
 {
 	struct http_parser_url u = {0};
 	bool has_scheme, has_host, has_port, has_path, has_query, has_userinfo;
-	git_buf scheme = GIT_BUF_INIT,
-		host = GIT_BUF_INIT,
-		port = GIT_BUF_INIT,
-		path = GIT_BUF_INIT,
-		username = GIT_BUF_INIT,
-		password = GIT_BUF_INIT,
-		query = GIT_BUF_INIT;
+	git_str scheme = GIT_STR_INIT,
+		host = GIT_STR_INIT,
+		port = GIT_STR_INIT,
+		path = GIT_STR_INIT,
+		username = GIT_STR_INIT,
+		password = GIT_STR_INIT,
+		query = GIT_STR_INIT;
 	int error = GIT_EINVALIDSPEC;
 
 	if (http_parser_parse_url(given, strlen(given), false, &u)) {
@@ -103,7 +103,7 @@ int git_net_url_parse(git_net_url *url, const char *given)
 	if (has_scheme) {
 		const char *url_scheme = given + u.field_data[UF_SCHEMA].off;
 		size_t url_scheme_len = u.field_data[UF_SCHEMA].len;
-		git_buf_put(&scheme, url_scheme, url_scheme_len);
+		git_str_put(&scheme, url_scheme, url_scheme_len);
 		git__strntolower(scheme.ptr, scheme.size);
 	} else {
 		git_error_set(GIT_ERROR_NET, "malformed URL '%s'", given);
@@ -113,13 +113,13 @@ int git_net_url_parse(git_net_url *url, const char *given)
 	if (has_host) {
 		const char *url_host = given + u.field_data[UF_HOST].off;
 		size_t url_host_len = u.field_data[UF_HOST].len;
-		git_buf_decode_percent(&host, url_host, url_host_len);
+		git_str_decode_percent(&host, url_host, url_host_len);
 	}
 
 	if (has_port) {
 		const char *url_port = given + u.field_data[UF_PORT].off;
 		size_t url_port_len = u.field_data[UF_PORT].len;
-		git_buf_put(&port, url_port, url_port_len);
+		git_str_put(&port, url_port, url_port_len);
 	} else {
 		const char *default_port = default_port_for_scheme(scheme.ptr);
 
@@ -128,21 +128,21 @@ int git_net_url_parse(git_net_url *url, const char *given)
 			goto done;
 		}
 
-		git_buf_puts(&port, default_port);
+		git_str_puts(&port, default_port);
 	}
 
 	if (has_path) {
 		const char *url_path = given + u.field_data[UF_PATH].off;
 		size_t url_path_len = u.field_data[UF_PATH].len;
-		git_buf_put(&path, url_path, url_path_len);
+		git_str_put(&path, url_path, url_path_len);
 	} else {
-		git_buf_puts(&path, "/");
+		git_str_puts(&path, "/");
 	}
 
 	if (has_query) {
 		const char *url_query = given + u.field_data[UF_QUERY].off;
 		size_t url_query_len = u.field_data[UF_QUERY].len;
-		git_buf_decode_percent(&query, url_query, url_query_len);
+		git_str_decode_percent(&query, url_query, url_query_len);
 	}
 
 	if (has_userinfo) {
@@ -156,40 +156,40 @@ int git_net_url_parse(git_net_url *url, const char *given)
 			const char *url_password = colon + 1;
 			size_t url_password_len = url_userinfo_len - (url_username_len + 1);
 
-			git_buf_decode_percent(&username, url_username, url_username_len);
-			git_buf_decode_percent(&password, url_password, url_password_len);
+			git_str_decode_percent(&username, url_username, url_username_len);
+			git_str_decode_percent(&password, url_password, url_password_len);
 		} else {
-			git_buf_decode_percent(&username, url_userinfo, url_userinfo_len);
+			git_str_decode_percent(&username, url_userinfo, url_userinfo_len);
 		}
 	}
 
-	if (git_buf_oom(&scheme) ||
-	    git_buf_oom(&host) ||
-	    git_buf_oom(&port) ||
-	    git_buf_oom(&path) ||
-	    git_buf_oom(&query) ||
-	    git_buf_oom(&username) ||
-	    git_buf_oom(&password))
+	if (git_str_oom(&scheme) ||
+	    git_str_oom(&host) ||
+	    git_str_oom(&port) ||
+	    git_str_oom(&path) ||
+	    git_str_oom(&query) ||
+	    git_str_oom(&username) ||
+	    git_str_oom(&password))
 		return -1;
 
-	url->scheme = git_buf_detach(&scheme);
-	url->host = git_buf_detach(&host);
-	url->port = git_buf_detach(&port);
-	url->path = git_buf_detach(&path);
-	url->query = git_buf_detach(&query);
-	url->username = git_buf_detach(&username);
-	url->password = git_buf_detach(&password);
+	url->scheme = git_str_detach(&scheme);
+	url->host = git_str_detach(&host);
+	url->port = git_str_detach(&port);
+	url->path = git_str_detach(&path);
+	url->query = git_str_detach(&query);
+	url->username = git_str_detach(&username);
+	url->password = git_str_detach(&password);
 
 	error = 0;
 
 done:
-	git_buf_dispose(&scheme);
-	git_buf_dispose(&host);
-	git_buf_dispose(&port);
-	git_buf_dispose(&path);
-	git_buf_dispose(&query);
-	git_buf_dispose(&username);
-	git_buf_dispose(&password);
+	git_str_dispose(&scheme);
+	git_str_dispose(&host);
+	git_str_dispose(&port);
+	git_str_dispose(&path);
+	git_str_dispose(&query);
+	git_str_dispose(&username);
+	git_str_dispose(&password);
 	return error;
 }
 
@@ -198,7 +198,7 @@ int git_net_url_joinpath(
 	git_net_url *one,
 	const char *two)
 {
-	git_buf path = GIT_BUF_INIT;
+	git_str path = GIT_STR_INIT;
 	const char *query;
 	size_t one_len, two_len;
 
@@ -226,14 +226,14 @@ int git_net_url_joinpath(
 		two_len--;
 	}
 
-	git_buf_put(&path, one->path, one_len);
-	git_buf_putc(&path, '/');
-	git_buf_put(&path, two, two_len);
+	git_str_put(&path, one->path, one_len);
+	git_str_putc(&path, '/');
+	git_str_put(&path, two, two_len);
 
-	if (git_buf_oom(&path))
+	if (git_str_oom(&path))
 		return -1;
 
-	out->path = git_buf_detach(&path);
+	out->path = git_str_detach(&path);
 
 	if (one->scheme) {
 		out->scheme = git__strdup(one->scheme);
@@ -399,53 +399,53 @@ void git_net_url_swap(git_net_url *a, git_net_url *b)
 	memcpy(b, &tmp, sizeof(git_net_url));
 }
 
-int git_net_url_fmt(git_buf *buf, git_net_url *url)
+int git_net_url_fmt(git_str *buf, git_net_url *url)
 {
 	GIT_ASSERT_ARG(url);
 	GIT_ASSERT_ARG(url->scheme);
 	GIT_ASSERT_ARG(url->host);
 
-	git_buf_puts(buf, url->scheme);
-	git_buf_puts(buf, "://");
+	git_str_puts(buf, url->scheme);
+	git_str_puts(buf, "://");
 
 	if (url->username) {
-		git_buf_puts(buf, url->username);
+		git_str_puts(buf, url->username);
 
 		if (url->password) {
-			git_buf_puts(buf, ":");
-			git_buf_puts(buf, url->password);
+			git_str_puts(buf, ":");
+			git_str_puts(buf, url->password);
 		}
 
-		git_buf_putc(buf, '@');
+		git_str_putc(buf, '@');
 	}
 
-	git_buf_puts(buf, url->host);
+	git_str_puts(buf, url->host);
 
 	if (url->port && !git_net_url_is_default_port(url)) {
-		git_buf_putc(buf, ':');
-		git_buf_puts(buf, url->port);
+		git_str_putc(buf, ':');
+		git_str_puts(buf, url->port);
 	}
 
-	git_buf_puts(buf, url->path ? url->path : "/");
+	git_str_puts(buf, url->path ? url->path : "/");
 
 	if (url->query) {
-		git_buf_putc(buf, '?');
-		git_buf_puts(buf, url->query);
+		git_str_putc(buf, '?');
+		git_str_puts(buf, url->query);
 	}
 
-	return git_buf_oom(buf) ? -1 : 0;
+	return git_str_oom(buf) ? -1 : 0;
 }
 
-int git_net_url_fmt_path(git_buf *buf, git_net_url *url)
+int git_net_url_fmt_path(git_str *buf, git_net_url *url)
 {
-	git_buf_puts(buf, url->path ? url->path : "/");
+	git_str_puts(buf, url->path ? url->path : "/");
 
 	if (url->query) {
-		git_buf_putc(buf, '?');
-		git_buf_puts(buf, url->query);
+		git_str_putc(buf, '?');
+		git_str_puts(buf, url->query);
 	}
 
-	return git_buf_oom(buf) ? -1 : 0;
+	return git_str_oom(buf) ? -1 : 0;
 }
 
 static bool matches_pattern(