Add a library that allows commands to produce structured output in any
of a range of formats using a single API.
The API includes an OPT_OUTPUT and handle_output_arg so that the
option handling for different commands will be as similar as possible.
At the moment JSON and XML output options are available - though the
XML output is _very_ rudimentary.
Signed-off-by: Julian Phillips <julian@xxxxxxxxxxxxxxxxx>
---
Makefile | 3 +
output-json.c | 128 ++++++++++++++++++++++++++++++++++
output-xml.c | 68 ++++++++++++++++++
output.c | 212 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++
output.h | 71 +++++++++++++++++++
5 files changed, 482 insertions(+), 0 deletions(-)
create mode 100644 output-json.c
create mode 100644 output-xml.c
create mode 100644 output.c
create mode 100644 output.h
diff --git a/Makefile b/Makefile
index 910f471..4ba2a4f 100644
--- a/Makefile
+++ b/Makefile
@@ -576,6 +576,9 @@ LIB_OBJS += merge-recursive.o
LIB_OBJS += name-hash.o
LIB_OBJS += notes.o
LIB_OBJS += object.o
+LIB_OBJS += output.o
+LIB_OBJS += output-json.o
+LIB_OBJS += output-xml.o
LIB_OBJS += pack-check.o
LIB_OBJS += pack-refs.o
LIB_OBJS += pack-revindex.o
diff --git a/output-json.c b/output-json.c
new file mode 100644
index 0000000..0eb66b2
--- /dev/null
+++ b/output-json.c
@@ -0,0 +1,128 @@
+#include "git-compat-util.h"
+#include "output.h"
+#include "strbuf.h"
+
+static char *json_quote(char *s)
+{
+ struct strbuf buf = STRBUF_INIT;
+
+ while (*s) {
+ switch (*s) {
+ case '"':
+ strbuf_addstr(&buf, "\\\"");
+ break;
+ case '\\':
+ strbuf_addstr(&buf, "\\\\");
+ break;
+ case '\b':
+ strbuf_addstr(&buf, "\\b");
+ break;
+ case '\f':
+ strbuf_addstr(&buf, "\\f");
+ break;
+ case '\n':
+ strbuf_addstr(&buf, "\\n");
+ break;
+ case '\r':
+ strbuf_addstr(&buf, "\\r");
+ break;
+ case '\t':
+ strbuf_addstr(&buf, "\\t");
+ break;
+ default:
+ /* All control characters must be encode, even if they
+ * don't have a specific escape character of their own */
+ if (*s < 0x20)
+ strbuf_addf(&buf, "\\u%04x", *s);
+ else
+ strbuf_addch(&buf, *s);
+ break;
+ }
+ s++;
+ }
+
+ return strbuf_detach(&buf, NULL);
+}
+
+static void json_obj_start(FILE *file, char *name)
+{
+ fprintf(file, "{\n");
+}
+
+static void json_obj_end(FILE *file, char *name)
+{
+ fprintf(file, "\n}");
+}
+
+static void json_obj_item_start(FILE *file, char *name, int first)
+{
+ char *quoted = json_quote(name);
+ if (!first)
+ fprintf(file, ",\n");
+ fprintf(file, "\"%s\" : ", quoted);
+ free(quoted);
+}
+
+static void json_array_start(FILE *file, char *name)
+{
+ fprintf(file, "[\n");
+}
+
+static void json_array_end(FILE *file, char *name)
+{
+ fprintf(file, "\n]");
+}
+
+static void json_array_item_start(FILE *file, char *name, int first)
+{
+ if (!first)
+ fprintf(file, ",\n");
+}
+
+static void json_bool(FILE *file, int value)
+{
+ if (value)
+ fprintf(file, "true");
+ else
+ fprintf(file, "false");
+}
+
+static void json_str(FILE *file, char *value)
+{
+ char *quoted = json_quote(value);
+ fprintf(file, "\"%s\"", quoted);
+ free(quoted);
+}
+
+static void json_int(FILE *file, int64_t value)
+{
+ fprintf(file, "%lld", value);
+}
+
+static void json_uint(FILE *file, uint64_t value)
+{
+ fprintf(file, "%llu", value);
+}
+
+static void json_double(FILE *file, double value, int precision)
+{
+ fprintf(file, "%.*f", precision, value);
+}
+
+struct output_ops output_json_ops = {
+ json_obj_start,
+ json_obj_end,
+ json_obj_item_start,
+ NULL,
+
+ json_array_start,
+ json_array_end,
+ json_array_item_start,
+ NULL,
+
+ json_bool,
+ json_str,
+ json_int,
+ json_uint,
+ json_double,
+};
diff --git a/output-xml.c b/output-xml.c
new file mode 100644
index 0000000..50dd7d6
--- /dev/null
+++ b/output-xml.c
@@ -0,0 +1,68 @@
+#include "git-compat-util.h"
+#include "output.h"
+
+static void xml_obj_start(FILE *file, char *name)
+{
+ fprintf(file, "<object name=\"%s\">\n", name);
+}
+
+static void xml_obj_end(FILE *file, char *name)
+{
+ fprintf(file, "</object>\n");
+}
+
+static void xml_obj_item_start(FILE *file, char *name, int first)
+{
+ fprintf(file, "<%s>", name);
+}
+
+static void xml_obj_item_end(FILE *file, char *name, int first)
+{
+ fprintf(file, "</%s>\n", name);
+}
+
+static void xml_bool(FILE *file, int value)
+{
+ if (value)
+ fprintf(file, "true");
+ else
+ fprintf(file, "false");
+}
+
+static void xml_str(FILE *file, char *value)
+{
+ fprintf(file, "\"%s\"", value);
+}
+
+static void xml_int(FILE *file, int64_t value)
+{
+ fprintf(file, "%lld", value);
+}
+
+static void xml_uint(FILE *file, uint64_t value)
+{
+ fprintf(file, "%llu", value);
+}
+
+static void xml_double(FILE *file, double value, int precision)
+{
+ fprintf(file, "%.*f", precision, value);
+}
+
+struct output_ops output_xml_ops = {
+ xml_obj_start,
+ xml_obj_end,
+ xml_obj_item_start,
+ xml_obj_item_end,
+
+ NULL,
+ NULL,
+ NULL,
+ NULL,
+
+ xml_bool,
+ xml_str,
+ xml_int,
+ xml_uint,
+ xml_double,
+};
diff --git a/output.c b/output.c
new file mode 100644
index 0000000..305428c
--- /dev/null
+++ b/output.c
@@ -0,0 +1,212 @@
+#include "git-compat-util.h"
+#include "output.h"
+#include "strbuf.h"
+
+#define DEFAULT_OUTPUT_FORMAT OUTPUT_JSON
+
+extern struct output_ops output_json_ops;
+extern struct output_ops output_xml_ops;
+
+struct output_ops *output_ops[] = {
+ NULL, /* OUTPUT_NORMAL */
+ &output_json_ops,
+ &output_xml_ops,
+};
+
+enum output_style handle_output_arg(char *s)
+{
+ if (!s)
+ return OUTPUT_NORMAL;
+ else if (!strcmp(s, "no"))
+ return OUTPUT_NORMAL;
+ else if (!strcmp(s, "json"))
+ return OUTPUT_JSON;
+ else if (!strcmp(s, "xml"))
+ return OUTPUT_XML;
+ else
+ die("Invalid output style '%s'", s);
+}
+
+char *output_supported_styles()
+{
+ return "";
+}
+
+struct output_context *output_start(enum output_style style)
+{
+ struct output_context *context = xmallocz(sizeof(*context));
+
+ context->style = style;
+ context->file = stdout;
+ context->ops = output_ops[style];
+
+ output_start_object(context, "git");
+
+ return context;
+}
+
+void output_end(struct output_context *context)
+{
+ while(context->current)
+ output_end_current(context);
+
+ fprintf(context->file, "\n");
+
+ free(context);
+}
+
+
+static void item_start(struct output_context *context, char *name)
+{
+ if (!context->current)
+ return;
+
+ switch (context->current->type) {
+ case OUTPUT_ITEM_OBJECT:
+ if (context->ops->obj_item_start)
+ context->ops->obj_item_start(context->file, name,
+ context->current->first);
+ break;
+ case OUTPUT_ITEM_ARRAY:
+ if (context->ops->array_item_start)
+ context->ops->array_item_start(context->file, name,
+ context->current->first);
+ break;
+ }
+}
+
+static void item_end(struct output_context *context, char *name)
+{
+ if (!context->current)
+ return;
+
+ switch (context->current->type) {
+ case OUTPUT_ITEM_OBJECT:
+ if (context->ops->obj_item_end)
+ context->ops->obj_item_end(context->file, name,
+ context->current->first);
+ break;
+ case OUTPUT_ITEM_ARRAY:
+ if (context->ops->array_item_end)
+ context->ops->array_item_end(context->file, name,
+ context->current->first);
+ break;
+ }
+
+ context->current->first = 0;
+}
+
+
+void output_new_current(struct output_context *context, char *name,
+ enum output_item_type type)
+{
+ struct output_item *item = xmallocz(sizeof(*item));
+
+ item->name = xstrdup(name);
+ item->type = type;
+ item->first = 1;
+
+ item->prev = context->current;
+ context->current = item;
+}
+
+void output_start_object(struct output_context *context, char *name)
+{
+ item_start(context, name);
+
+ output_new_current(context, name, OUTPUT_ITEM_OBJECT);
+
+ if (context->ops->obj_start)
+ context->ops->obj_start(context->file, name);
+}
+
+void output_start_array(struct output_context *context, char *name)
+{
+ item_start(context, name);
+
+ output_new_current(context, name, OUTPUT_ITEM_ARRAY);
+
+ if (context->ops->array_start)
+ context->ops->array_start(context->file, name);
+}
+
+void output_end_current(struct output_context *context)
+{
+ struct output_item *item = context->current;
+
+ switch (item->type) {
+ case OUTPUT_ITEM_OBJECT:
+ if (context->ops->obj_end)
+ context->ops->obj_end(context->file, item->name);
+ break;
+ case OUTPUT_ITEM_ARRAY:
+ if (context->ops->array_end)
+ context->ops->array_end(context->file, item->name);
+ break;
+ }
+
+ item = context->current;
+ context->current = context->current->prev;
+
+ item_end(context, item->name);
+
+ free(item->name);
+ free(item);
+}
+
+
+void output_bool(struct output_context *context, char *name, int value)
+{
+ item_start(context, name);
+ if (context->ops->bool)
+ context->ops->bool(context->file, value);
+ item_end(context, name);
+}
+
+void output_str(struct output_context *context, char *name, char *value)
+{
+ item_start(context, name);
+ if (context->ops->str)
+ context->ops->str(context->file, value);
+ item_end(context, name);
+}
+
+void output_strf(struct output_context *context, char *name, char *fmt, ...)
+{
+ struct strbuf buf = STRBUF_INIT;
+ va_list ap;
+
+ va_start(ap, fmt);
+ strbuf_vaddf(&buf, fmt, ap);
+ va_end(ap);
+
+ output_str(context, name, buf.buf);
+
+ strbuf_release(&buf);
+}
+
+void output_int(struct output_context *context, char *name, int64_t value)
+{
+ item_start(context, name);
+ if (context->ops->int_)
+ context->ops->int_(context->file, value);
+ item_end(context, name);
+}
+
+void output_uint(struct output_context *context, char *name, uint64_t value)
+{
+ item_start(context, name);
+ if (context->ops->uint)
+ context->ops->uint(context->file, value);
+ item_end(context, name);
+}
+
+void output_double(struct output_context *context, char *name, double value,
+ int precision)
+{
+ item_start(context, name);
+ if (context->ops->double_)
+ context->ops->double_(context->file, value, precision);
+ item_end(context, name);
+}
+
diff --git a/output.h b/output.h
new file mode 100644
index 0000000..9472ae4
--- /dev/null
+++ b/output.h
@@ -0,0 +1,71 @@
+#ifndef OUTPUT_H
+#define OUTPUT_H
+
+enum output_style {
+ OUTPUT_NORMAL,
+ OUTPUT_JSON,
+ OUTPUT_XML,
+};
+
+struct output_ops {
+ void (*obj_start)(FILE *file, char *name);
+ void (*obj_end)(FILE *file, char *name);
+ void (*obj_item_start)(FILE *file, char *name, int first);
+ void (*obj_item_end)(FILE *file, char *name, int first);
+
+ void (*array_start)(FILE *file, char *name);
+ void (*array_end)(FILE *file, char *name);
+ void (*array_item_start)(FILE *file, char *name, int first);
+ void (*array_item_end)(FILE *file, char *name, int first);
+
+ void (*bool)(FILE *file, int value);
+ void (*str)(FILE *file, char *value);
+ void (*int_)(FILE *file, int64_t value);
+ void (*uint)(FILE *file, uint64_t value);
+ void (*double_)(FILE *file, double value, int precision);
+};
+
+enum output_item_type {
+ OUTPUT_ITEM_OBJECT,
+ OUTPUT_ITEM_ARRAY,
+};
+
+struct output_item {
+ struct output_item *prev;
+ char *name;
+ enum output_item_type type;
+ int first;
+};
+
+struct output_context {
+ enum output_style style;
+ FILE *file;
+ struct output_ops *ops;
+ struct output_item *current;
+};
+
+extern struct option OUTPUT_OPTION;
+
+#define OPT_OUTPUT(s, l, v) { OPTION_STRING, (s), (l), (v), "style", \
+ "Use a structured output style, options: " \
+ "no, json, xml (Default: no)", \
+ PARSE_OPT_OPTARG, NULL, (intptr_t)"no" }
+
+enum output_style handle_output_arg(char *s);
+
+struct output_context *output_start(enum output_style style);
+void output_end(struct output_context *context);
+
+void output_start_object(struct output_context *context, char *name);
+void output_start_array(struct output_context *context, char *name);
+void output_end_current(struct output_context *context);
+
+void output_bool(struct output_context *context, char *name, int value);
+void output_str(struct output_context *context, char *name, char *value);
+void output_strf(struct output_context *context, char *name, char *fmt, ...);
+void output_int(struct output_context *context, char *name, int64_t value);
+void output_uint(struct output_context *context, char *name, uint64_t value);
+void output_double(struct output_context *context, char *name, double value,
+ int precision);
+
+#endif /* OUTPUT_H */
--
1.7.0.4
--
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