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authorJohn Estabrook <jestabro@vyos.io>2020-08-28 15:50:12 -0500
committerJohn Estabrook <jestabro@vyos.io>2020-08-31 09:57:00 -0500
commit163047aedabc2d43249239b0c0bdf92b8e664131 (patch)
tree097147c823c5dab2c3f041af430939084f68b682 /src/shim/mkjson/mkjson.c
parent88985dad133d5e85aca559dbfce53207a2292e0a (diff)
downloadvyos-1x-163047aedabc2d43249239b0c0bdf92b8e664131.tar.gz
vyos-1x-163047aedabc2d43249239b0c0bdf92b8e664131.zip
configd: T2582: add mkjson for use by shim
(https://github.com/Jacajack/mkjson.git)
Diffstat (limited to 'src/shim/mkjson/mkjson.c')
-rw-r--r--src/shim/mkjson/mkjson.c307
1 files changed, 307 insertions, 0 deletions
diff --git a/src/shim/mkjson/mkjson.c b/src/shim/mkjson/mkjson.c
new file mode 100644
index 000000000..1172664fb
--- /dev/null
+++ b/src/shim/mkjson/mkjson.c
@@ -0,0 +1,307 @@
+/* mkjson.c - a part of mkjson library
+ *
+ * Copyright (C) 2018 Jacek Wieczorek
+ *
+ * This software may be modified and distributed under the terms
+ * of the MIT license. See the LICENSE file for details.
+ */
+
+#include <mkjson.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <stdarg.h>
+#include <string.h>
+
+// Works like asprintf, but it's always there
+// I don't want the name to collide with anything
+static int allsprintf( char **strp, const char *fmt, ... )
+{
+ int len;
+ va_list ap;
+ va_start( ap, fmt );
+
+ #ifdef _GNU_SOURCE
+ // Just hand everything to vasprintf, if it's available
+ len = vasprintf( strp, fmt, ap );
+ #else
+ // Or do it the manual way
+ char *buf;
+ len = vsnprintf( NULL, 0, fmt, ap );
+ if ( len >= 0 )
+ {
+ buf = malloc( ++len );
+ if ( buf != NULL )
+ {
+ // Hopefully, that's the right way to do it
+ va_end( ap );
+ va_start( ap, fmt );
+
+ // Write and return the data
+ len = vsnprintf( buf, len, fmt, ap );
+ if ( len >= 0 )
+ {
+ *strp = buf;
+ }
+ else
+ {
+ free( buf );
+ }
+ }
+ }
+ #endif
+
+ va_end( ap );
+ return len;
+}
+
+// Return JSON string built from va_arg arguments
+// If no longer needed, should be passed to free() by user
+char *mkjson( enum mkjson_container_type otype, int count, ... )
+{
+ int i, len, goodchunks = 0, failure = 0;
+ char *json, *prefix, **chunks, ign;
+
+ // Value - type and data
+ enum mkjson_value_type vtype;
+ const char *key;
+ long long int intval;
+ long double dblval;
+ const char *strval;
+
+ // Since v0.9 count cannot be a negative value and datatype is indicated by a separate argument
+ // Since I'm not sure whether it's right to put assertions in libraries, the next line is commented out
+ // assert( count >= 0 && "After v0.9 negative count is prohibited; please use otype argument instead" );
+ if ( count < 0 || ( otype != MKJSON_OBJ && otype != MKJSON_ARR ) ) return NULL;
+
+ // Allocate chunk pointer array - on standard platforms each one should be NULL
+ chunks = calloc( count, sizeof( char* ) );
+ if ( chunks == NULL ) return NULL;
+
+ // This should rather be at the point of no return
+ va_list ap;
+ va_start( ap, count );
+
+ // Create chunks
+ for ( i = 0; i < count && !failure; i++ )
+ {
+ // Get value type
+ vtype = va_arg( ap, enum mkjson_value_type );
+
+ // Get key
+ if ( otype == MKJSON_OBJ )
+ {
+ key = va_arg( ap, char* );
+ if ( key == NULL )
+ {
+ failure = 1;
+ break;
+ }
+ }
+ else key = "";
+
+ // Generate prefix
+ if ( allsprintf( &prefix, "%s%s%s",
+ otype == MKJSON_OBJ ? "\"" : "", // Quote before key
+ key, // Key
+ otype == MKJSON_OBJ ? "\": " : "" ) == -1 ) // Quote and colon after key
+ {
+ failure = 1;
+ break;
+ }
+
+ // Depending on value type
+ ign = 0;
+ switch ( vtype )
+ {
+ // Ignore string / JSON data
+ case MKJSON_IGN_STRING:
+ case MKJSON_IGN_JSON:
+ (void) va_arg( ap, const char* );
+ ign = 1;
+ break;
+
+ // Ignore string / JSON data and pass the pointer to free
+ case MKJSON_IGN_STRING_FREE:
+ case MKJSON_IGN_JSON_FREE:
+ free( va_arg( ap, char* ) );
+ ign = 1;
+ break;
+
+ // Ignore int / long long int
+ case MKJSON_IGN_INT:
+ case MKJSON_IGN_LLINT:
+ if ( vtype == MKJSON_IGN_INT )
+ (void) va_arg( ap, int );
+ else
+ (void) va_arg( ap, long long int );
+ ign = 1;
+ break;
+
+ // Ignore double / long double
+ case MKJSON_IGN_DOUBLE:
+ case MKJSON_IGN_LDOUBLE:
+ if ( vtype == MKJSON_IGN_DOUBLE )
+ (void) va_arg( ap, double );
+ else
+ (void) va_arg( ap, long double );
+ ign = 1;
+ break;
+
+ // Ignore boolean
+ case MKJSON_IGN_BOOL:
+ (void) va_arg( ap, int );
+ ign = 1;
+ break;
+
+ // Ignore null value
+ case MKJSON_IGN_NULL:
+ ign = 1;
+ break;
+
+ // A null-terminated string
+ case MKJSON_STRING:
+ case MKJSON_STRING_FREE:
+ strval = va_arg( ap, const char* );
+
+ // If the pointer points to NULL, the string will be replaced with JSON null value
+ if ( strval == NULL )
+ {
+ if ( allsprintf( chunks + i, "%snull", prefix ) == -1 )
+ chunks[i] = NULL;
+ }
+ else
+ {
+ if ( allsprintf( chunks + i, "%s\"%s\"", prefix, strval ) == -1 )
+ chunks[i] = NULL;
+ }
+
+ // Optional free
+ if ( vtype == MKJSON_STRING_FREE )
+ free( (char*) strval );
+ break;
+
+ // Embed JSON data
+ case MKJSON_JSON:
+ case MKJSON_JSON_FREE:
+ strval = va_arg( ap, const char* );
+
+ // If the pointer points to NULL, the JSON data is replaced with null value
+ if ( allsprintf( chunks + i, "%s%s", prefix, strval == NULL ? "null" : strval ) == -1 )
+ chunks[i] = NULL;
+
+ // Optional free
+ if ( vtype == MKJSON_JSON_FREE )
+ free( (char*) strval );
+ break;
+
+ // int / long long int
+ case MKJSON_INT:
+ case MKJSON_LLINT:
+ if ( vtype == MKJSON_INT )
+ intval = va_arg( ap, int );
+ else
+ intval = va_arg( ap, long long int );
+
+ if ( allsprintf( chunks + i, "%s%Ld", prefix, intval ) == -1 ) chunks[i] = NULL;
+ break;
+
+ // double / long double
+ case MKJSON_DOUBLE:
+ case MKJSON_LDOUBLE:
+ if ( vtype == MKJSON_DOUBLE )
+ dblval = va_arg( ap, double );
+ else
+ dblval = va_arg( ap, long double );
+
+ if ( allsprintf( chunks + i, "%s%Lf", prefix, dblval ) == -1 ) chunks[i] = NULL;
+ break;
+
+ // double / long double
+ case MKJSON_SCI_DOUBLE:
+ case MKJSON_SCI_LDOUBLE:
+ if ( vtype == MKJSON_SCI_DOUBLE )
+ dblval = va_arg( ap, double );
+ else
+ dblval = va_arg( ap, long double );
+
+ if ( allsprintf( chunks + i, "%s%Le", prefix, dblval ) == -1 ) chunks[i] = NULL;
+ break;
+
+ // Boolean
+ case MKJSON_BOOL:
+ intval = va_arg( ap, int );
+ if ( allsprintf( chunks + i, "%s%s", prefix, intval ? "true" : "false" ) == -1 ) chunks[i] = NULL;
+ break;
+
+ // JSON null
+ case MKJSON_NULL:
+ if ( allsprintf( chunks + i, "%snull", prefix ) == -1 ) chunks[i] = NULL;
+ break;
+
+ // Bad type specifier
+ default:
+ chunks[i] = NULL;
+ break;
+ }
+
+ // Free prefix memory
+ free( prefix );
+
+ // NULL chunk without ignore flag indicates failure
+ if ( !ign && chunks[i] == NULL ) failure = 1;
+
+ // NULL chunk now indicates ignore flag
+ if ( ign ) chunks[i] = NULL;
+ else goodchunks++;
+ }
+
+ // We won't use ap anymore
+ va_end( ap );
+
+ // If everything is fine, merge chunks and create full JSON table
+ if ( !failure )
+ {
+ // Get total length (this is without NUL byte)
+ len = 0;
+ for ( i = 0; i < count; i++ )
+ if ( chunks[i] != NULL )
+ len += strlen( chunks[i] );
+
+ // Total length = Chunks length + 2 brackets + separators
+ if ( goodchunks == 0 ) goodchunks = 1;
+ len = len + 2 + ( goodchunks - 1 ) * 2;
+
+ // Allocate memory for the whole thing
+ json = calloc( len + 1, sizeof( char ) );
+ if ( json != NULL )
+ {
+ // Merge chunks (and do not overwrite the first bracket)
+ for ( i = 0; i < count; i++ )
+ {
+ // Add separators:
+ // - not on the begining
+ // - always after valid chunk
+ // - between two valid chunks
+ // - between valid and ignored chunk if the latter isn't the last one
+ if ( i != 0 && chunks[i - 1] != NULL && ( chunks[i] != NULL || ( chunks[i] == NULL && i != count - 1 ) ) )
+ strcat( json + 1, ", ");
+
+ if ( chunks[i] != NULL )
+ strcat( json + 1, chunks[i] );
+ }
+
+ // Add proper brackets
+ json[0] = otype == MKJSON_OBJ ? '{' : '[';
+ json[len - 1] = otype == MKJSON_OBJ ? '}' : ']';
+ }
+ }
+ else json = NULL;
+
+ // Free chunks
+ for ( i = 0; i < count; i++ )
+ free( chunks[i] );
+ free( chunks );
+
+ return json;
+}
+