GopherProxy

	refactor to make it easier to use as a "library". handle errors more gracefully…
	git clone git://git.codemadness.org/json2tsv
	Log
	Files
	Refs
	README
	LICENSE
	---
	commit f831a4b76c10d7efcb72effd18332f3deac7a4fa
	parent 111c9cc55cbabc01fa14e8b7694be0ef940d1702
	Author: Hiltjo Posthuma <[email protected]>
	Date: Sat, 5 Oct 2019 22:30:49 +0200

	refactor to make it easier to use as a "library". handle errors more gracefully

	Diffstat:
	M json2tsv.c \| 114 ++++++++++++++++++-----------…

	1 file changed, 67 insertions(+), 47 deletions(-)
	---
	diff --git a/json2tsv.c b/json2tsv.c
	@@ -1,4 +1,5 @@
	#include <ctype.h>
	+#include <errno.h>
	#include <stdint.h>
	#include <stdio.h>
	#include <stdlib.h>
	@@ -31,13 +32,6 @@ struct json_node {

	static int showindices = 0; /* -n flag: show indices count for arrays */

	-void
	-fatal(const char *s)
	-{
	- fputs(s, stderr);
	- exit(1);
	-}
	-
	int
	codepointtoutf8(long r, char *s)
	{
	@@ -80,35 +74,42 @@ hexdigit(int c)
	return 0;
	}

	-void
	+int
	capacity(char *value, size_t sz, size_t cur, size_t inc)
	{
	size_t need, newsiz;
	+ char *newp;

	/* check addition overflow */
	need = cur + inc;
	- if (cur > SIZE_MAX - need \|\| *sz > SIZE_MAX - 16384)
	- fatal("overflow\n");
	+ if (cur > SIZE_MAX - need \|\| *sz > SIZE_MAX - 16384) {
	+ errno = EOVERFLOW;
	+ return -1;
	+ }

	if (sz == 0 \|\| need > sz) {
	for (newsiz = *sz; newsiz < need; newsiz += 16384)
	;
	- if (!(value = realloc(value, newsiz)))
	- fatal("realloc\n");
	+ if (!(newp = realloc(*value, newsiz)))
	+ return -1; /* up to caller to free memory */
	+ *value = newp;
	*sz = newsiz;
	}
	+ return 0;
	}

	-void
	-parsejson(void (cb)(struct json_node , size_t, const char *))
	+int
	+parsejson(void (cb)(struct json_node , size_t, const char ), const char *e…
	{
	struct json_node nodes[JSON_MAX_NODE_DEPTH] = { 0 };
	- long cp;
	size_t depth = 0, v = 0, vz = 0;
	- int c, escape;
	+ long cp;
	+ int c, i, escape, ret = -1;
	char *value = NULL;

	- capacity(&(nodes[0].name), &(nodes[0].namesiz), 0, 1);
	+ *errstr = "cannot allocate enough memory";
	+ if (capacity(&(nodes[0].name), &(nodes[0].namesiz), 0, 1) == -1)
	+ goto end;
	nodes[0].name[0] = '\0';

	while ((c = GETNEXT()) != EOF) {
	@@ -120,10 +121,13 @@ parsejson(void (cb)(struct json_node , size_t, const ch…
	case ':':
	nodes[depth].type = TYPE_PRIMITIVE;
	if (v) {
	- if (!depth \|\| nodes[depth - 1].type != TYPE_OB…
	- fatal("object member, but not in an ob…
	+ if (!depth \|\| nodes[depth - 1].type != TYPE_OB…
	+ *errstr = "object member, but not in a…
	+ goto end;
	+ }
	value[v] = '\0';
	- capacity(&(nodes[depth].name), &(nodes[depth].…
	+ if (capacity(&(nodes[depth].name), &(nodes[dep…
	+ goto end;
	memcpy(nodes[depth].name, value, v);
	nodes[depth].name[v] = '\0';
	v = 0;
	@@ -149,43 +153,43 @@ parsejson(void (cb)(struct json_node , size_t, const ch…
	case 'r': c = '\r'; break;
	case 't': c = '\t'; break;
	case 'u': /* hex hex hex hex */
	- if ((c = GETNEXT()) == EOF \|\| …
	- fatal("invalid codepoi…
	- cp = (hexdigit(c) << 12);
	- if ((c = GETNEXT()) == EOF \|\| …
	- fatal("invalid codepoi…
	- cp \|= (hexdigit(c) << 8);
	- if ((c = GETNEXT()) == EOF \|\| …
	- fatal("invalid codepoi…
	- cp \|= (hexdigit(c) << 4);
	- if ((c = GETNEXT()) == EOF \|\| …
	- fatal("invalid codepoi…
	- cp \|= (hexdigit(c));
	-
	- capacity(&value, &vz, v, 5);
	+ for (i = 12, cp = 0; i >= 0; i…
	+ if ((c = GETNEXT()) ==…
	+ *errstr = "inv…
	+ goto end;
	+ }
	+ cp \|= (hexdigit(c) << …
	+ }
	+ if (capacity(&value, &vz, v, 5…
	+ goto end;
	v += codepointtoutf8(cp, &valu…
	continue;
	default:
	continue; /* ignore unknown es…
	}
	- capacity(&value, &vz, v, 2);
	+ if (capacity(&value, &vz, v, 2) == -1)
	+ goto end;
	value[v++] = c;
	} else if (c == '\\') {
	escape = 1;
	} else if (c == '"') {
	break;
	} else {
	- capacity(&value, &vz, v, 2);
	+ if (capacity(&value, &vz, v, 2) == -1)
	+ goto end;
	value[v++] = c;
	}
	}
	- capacity(&value, &vz, v, 1);
	+ if (capacity(&value, &vz, v, 1) == -1)
	+ goto end;
	value[v] = '\0';
	break;
	case '[':
	case '{':
	- if (depth + 1 >= JSON_MAX_NODE_DEPTH)
	- fatal("max depth reached\n");
	+ if (depth + 1 >= JSON_MAX_NODE_DEPTH) {
	+ *errstr = "max node depth reached";
	+ goto end;
	+ }

	nodes[depth].index = 0;
	nodes[depth].type = c == '{' ? TYPE_OBJECT : TYPE_ARRA…
	@@ -195,7 +199,8 @@ parsejson(void (cb)(struct json_node , size_t, const char…

	depth++;
	nodes[depth].index = 0;
	- capacity(&(nodes[depth].name), &(nodes[depth].namesiz)…
	+ if (capacity(&(nodes[depth].name), &(nodes[depth].name…
	+ goto end;
	nodes[depth].name[0] = '\0';
	nodes[depth].type = TYPE_PRIMITIVE;
	break;
	@@ -211,8 +216,10 @@ parsejson(void (cb)(struct json_node , size_t, const cha…
	}
	if (!depth \|\|
	(nodes[depth - 1].type == TYPE_OBJECT && c == ']')…
	- (nodes[depth - 1].type == TYPE_ARRAY && c == '}'))
	- fatal("unbalanced nodes\n");
	+ (nodes[depth - 1].type == TYPE_ARRAY && c == '}'))…
	+ *errstr = "unbalanced nodes";
	+ goto end;
	+ }

	if (c == ']' \|\| c == '}') {
	nodes[--depth].index++;
	@@ -222,14 +229,20 @@ parsejson(void (cb)(struct json_node , size_t, const ch…
	}
	break;
	default:
	- capacity(&value, &vz, v, 2);
	+ if (capacity(&value, &vz, v, 2) == -1)
	+ goto end;
	value[v++] = c;
	}
	}

	+ ret = 0; /* success */
	+ *errstr = NULL;
	+end:
	for (depth = 0; depth < sizeof(nodes) / sizeof(nodes[0]); depth++)
	free(nodes[depth].name);
	free(value);
	+
	+ return ret;
	}

	void
	@@ -273,7 +286,7 @@ processnode(struct json_node *nodes, size_t depth, const ch…
	}

	switch (nodes[depth - 1].type) {
	- case TYPE_UNKNOWN: fatal("unknown type\n"); return;
	+ case TYPE_UNKNOWN: return;
	case TYPE_ARRAY: fputs("\ta\t\n", stdout); return;
	case TYPE_OBJECT: fputs("\to\t\n", stdout); return;
	case TYPE_PRIMITIVE: fputs("\tp\t", stdout); break;
	@@ -286,13 +299,20 @@ processnode(struct json_node *nodes, size_t depth, const …
	int
	main(int argc, char *argv[])
	{
	- if (pledge("stdio", NULL) == -1)
	- fatal("pledge stdio\n");
	+ const char *errstr;
	+
	+ if (pledge("stdio", NULL) == -1) {
	+ fprintf(stderr, "pledge stdio: %s\n", strerror(errno));
	+ return 1;
	+ }

	if (argc > 1 && argv[1][0] == '-' && argv[1][1] == 'n')
	showindices = 1;

	- parsejson(processnode);
	+ if (parsejson(processnode, &errstr) == -1) {
	+ fprintf(stderr, "error: %s\n", errstr);
	+ return 1;
	+ }

	return 0;
	}