diff options
Diffstat (limited to 'afb-utilities')
| -rw-r--r-- | afb-utilities/CMakeLists.txt | 37 | ||||
| -rw-r--r-- | afb-utilities/LICENSE | 201 | ||||
| -rw-r--r-- | afb-utilities/README.md | 11 | ||||
| -rw-r--r-- | afb-utilities/filescan-utils.c | 122 | ||||
| -rw-r--r-- | afb-utilities/filescan-utils.h | 45 | ||||
| -rw-r--r-- | afb-utilities/wrap-json.c | 939 | ||||
| -rw-r--r-- | afb-utilities/wrap-json.h | 46 | ||||
| -rw-r--r-- | afb-utilities/wrap-json.md | 305 |
8 files changed, 1706 insertions, 0 deletions
diff --git a/afb-utilities/CMakeLists.txt b/afb-utilities/CMakeLists.txt new file mode 100644 index 0000000..fe260fa --- /dev/null +++ b/afb-utilities/CMakeLists.txt @@ -0,0 +1,37 @@ +########################################################################### +# Copyright 2015, 2016, 2017 IoT.bzh +# +# author: Fulup Ar Foll <rfulup@iot.bzh> +# +# Licensed under the Apache License, Version 2.0 (the "License"); +# you may not use this file except in compliance with the License. +# You may obtain a copy of the License at +# +# http://www.apache.org/licenses/LICENSE-2.0 +# +# Unless required by applicable law or agreed to in writing, software +# distributed under the License is distributed on an "AS IS" BASIS, +# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. +# See the License for the specific language governing permissions and +# limitations under the License. +########################################################################### + +# This is a CMakeLists.txt file meant to be included as submodule into an AGL +# app using app-templates subdmodules + +# Add target to project dependency list +PROJECT_TARGET_ADD(afb-utilities) + + # Define targets + ADD_LIBRARY(${TARGET_NAME} STATIC wrap-json.c filescan-utils.c) + + # Library properties + SET_TARGET_PROPERTIES(${TARGET_NAME} PROPERTIES + OUTPUT_NAME ${TARGET_NAME} + ) + + # Define target includes + TARGET_INCLUDE_DIRECTORIES(${TARGET_NAME} + PUBLIC ${CMAKE_CURRENT_SOURCE_DIR} + ) + diff --git a/afb-utilities/LICENSE b/afb-utilities/LICENSE new file mode 100644 index 0000000..8dada3e --- /dev/null +++ b/afb-utilities/LICENSE @@ -0,0 +1,201 @@ + Apache License + Version 2.0, January 2004 + http://www.apache.org/licenses/ + + TERMS AND CONDITIONS FOR USE, REPRODUCTION, AND DISTRIBUTION + + 1. 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We also recommend that a + file or class name and description of purpose be included on the + same "printed page" as the copyright notice for easier + identification within third-party archives. + + Copyright {yyyy} {name of copyright owner} + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. diff --git a/afb-utilities/README.md b/afb-utilities/README.md new file mode 100644 index 0000000..03a0bcc --- /dev/null +++ b/afb-utilities/README.md @@ -0,0 +1,11 @@ +AFB Utilities +============= + +You should find useful utilities to integrates as submodule in your bindings +development. + +From your AFB apps repository do the following to integrates this repo: + +```bash +git submodule add git@github.com:iotbzh/afb-utilities +``` diff --git a/afb-utilities/filescan-utils.c b/afb-utilities/filescan-utils.c new file mode 100644 index 0000000..46e461b --- /dev/null +++ b/afb-utilities/filescan-utils.c @@ -0,0 +1,122 @@ +/* + * Copyright (C) 2016 "IoT.bzh" + * Author Fulup Ar Foll <fulup@iot.bzh> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + */ + +#define _GNU_SOURCE +#include <stdio.h> +#include <string.h> +#include <time.h> +#include <sys/prctl.h> +#include <dirent.h> + +#include "filescan-utils.h" + +// List Avaliable Configuration Files +PUBLIC json_object* ScanForConfig (const char* searchPath, CtlScanDirModeT mode, const char *pre, const char *ext) { + json_object *responseJ; + char *dirPath; + char* dirList= strdup(searchPath); + size_t extLen=0; + + void ScanDir (char *searchPath) { + DIR *dirHandle; + struct dirent *dirEnt; + dirHandle = opendir (searchPath); + if (!dirHandle) { + AFB_DEBUG ("CONFIG-SCANNING dir=%s not readable", searchPath); + return; + } + + //AFB_NOTICE ("CONFIG-SCANNING:ctl_listconfig scanning: %s", searchPath); + while ((dirEnt = readdir(dirHandle)) != NULL) { + + // recursively search embedded directories ignoring any directory starting by '.' or '_' + if (dirEnt->d_type == DT_DIR && mode == CTL_SCAN_RECURSIVE) { + char newpath[CONTROL_MAXPATH_LEN]; + if (dirEnt->d_name[0]=='.' || dirEnt->d_name[0]=='_') continue; + + strncpy(newpath, searchPath, sizeof(newpath)); + strncat(newpath, "/", sizeof(newpath)); + strncat(newpath, dirEnt->d_name, sizeof(newpath)); + ScanDir(newpath); + continue; + } + + // Unknown type is accepted to support dump filesystems + if (dirEnt->d_type == DT_REG || dirEnt->d_type == DT_UNKNOWN) { + + // check prefix and extention + size_t extIdx=strlen(dirEnt->d_name)-extLen; + if (extIdx <= 0) continue; + if (pre && !strcasestr (dirEnt->d_name, pre)) continue; + if (ext && strcasecmp (ext, &dirEnt->d_name[extIdx])) continue; + + struct json_object *pathJ = json_object_new_object(); + json_object_object_add(pathJ, "fullpath", json_object_new_string(searchPath)); + json_object_object_add(pathJ, "filename", json_object_new_string(dirEnt->d_name)); + json_object_array_add(responseJ, pathJ); + } + } + closedir(dirHandle); + } + + if (ext) extLen=strlen(ext); + responseJ = json_object_new_array(); + + // loop recursively on dir + for (dirPath= strtok(dirList, ":"); dirPath && *dirPath; dirPath=strtok(NULL,":")) { + ScanDir (dirPath); + } + + free (dirList); + return (responseJ); +} + +PUBLIC const char *GetMidleName(const char*name) { + char *fullname = strdup(name); + + for (int idx = 0; fullname[idx] != '\0'; idx++) { + int start; + if (fullname[idx] == '-') { + start = idx + 1; + for (int jdx = start; ; jdx++) { + if (fullname[jdx] == '-' || fullname[jdx] == '.' || fullname[jdx] == '\0') { + fullname[jdx] = '\0'; + return &fullname[start]; + break; + } + } + break; + } + } + return ""; +} + +PUBLIC const char *GetBinderName() { + char psName[17]; + static char *binderName=NULL; + + if (binderName) return binderName; + + binderName= getenv("AFB_BINDER_NAME"); + if (!binderName) { + // retrieve binder name from process name afb-name-trailer + prctl(PR_GET_NAME, psName,NULL,NULL,NULL); + binderName=(char*)GetMidleName(psName); + } + + return binderName; +} diff --git a/afb-utilities/filescan-utils.h b/afb-utilities/filescan-utils.h new file mode 100644 index 0000000..a97d030 --- /dev/null +++ b/afb-utilities/filescan-utils.h @@ -0,0 +1,45 @@ +/* + * Copyright (C) 2016 "IoT.bzh" + * Author Fulup Ar Foll <fulup@iot.bzh> + * + * Licensed under the Apache License, Version 2.0 (the "License"); + * you may not use this file except in compliance with the License. + * You may obtain a copy of the License at + * + * http://www.apache.org/licenses/LICENSE-2.0 + * + * Unless required by applicable law or agreed to in writing, software + * distributed under the License is distributed on an "AS IS" BASIS, + * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + * See the License for the specific language governing permissions and + * limitations under the License. + * + * reference: + * amixer contents; amixer controls; + * http://www.tldp.org/HOWTO/Alsa-sound-6.html + */ + +#ifndef FILESCAN_UTILS_H +#define FILESCAN_UTILS_H + +#define AFB_BINDING_VERSION 2 +#include <afb/afb-binding.h> +#include <json-c/json.h> + +#ifndef PUBLIC + #define PUBLIC +#endif +#define STATIC static + +// ctl-misc.c +typedef enum { + CTL_SCAN_FLAT=0, + CTL_SCAN_RECURSIVE=1, +} CtlScanDirModeT; + +PUBLIC const char *GetMidleName(const char*name); +PUBLIC const char *GetBinderName(); +PUBLIC json_object* ScanForConfig (const char* searchPath, CtlScanDirModeT mode, const char *pre, const char *ext); + +#endif /* FILESCAN_UTILS_H */ + diff --git a/afb-utilities/wrap-json.c b/afb-utilities/wrap-json.c new file mode 100644 index 0000000..164e127 --- /dev/null +++ b/afb-utilities/wrap-json.c @@ -0,0 +1,939 @@ +/* + Copyright (C) 2016, 2017 "IoT.bzh" + + author: José Bollo <jose.bollo@iot.bzh> + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. +*/ + +#include <string.h> + +#include "wrap-json.h" + +#define STACKCOUNT 32 +#define STRCOUNT 8 + +enum { + wrap_json_error_none, + wrap_json_error_null_object, + wrap_json_error_truncated, + wrap_json_error_internal_error, + wrap_json_error_out_of_memory, + wrap_json_error_invalid_character, + wrap_json_error_too_long, + wrap_json_error_too_deep, + wrap_json_error_null_spec, + wrap_json_error_null_key, + wrap_json_error_null_string, + wrap_json_error_out_of_range, + wrap_json_error_incomplete, + wrap_json_error_missfit_type, + wrap_json_error_key_not_found, + _wrap_json_error_count_ +}; + +static const char ignore_all[] = " \t\n\r,:"; +static const char pack_accept_arr[] = "][{snbiIfoO"; +static const char pack_accept_key[] = "s}"; +#define pack_accept_any (&pack_accept_arr[1]) + +static const char unpack_accept_arr[] = "*!][{snbiIfFoO"; +static const char unpack_accept_key[] = "*!s}"; +#define unpack_accept_any (&unpack_accept_arr[3]) + +static const char *pack_errors[_wrap_json_error_count_] = +{ + [wrap_json_error_none] = "unknown error", + [wrap_json_error_null_object] = "null object", + [wrap_json_error_truncated] = "truncated", + [wrap_json_error_internal_error] = "internal error", + [wrap_json_error_out_of_memory] = "out of memory", + [wrap_json_error_invalid_character] = "invalid character", + [wrap_json_error_too_long] = "too long", + [wrap_json_error_too_deep] = "too deep", + [wrap_json_error_null_spec] = "spec is NULL", + [wrap_json_error_null_key] = "key is NULL", + [wrap_json_error_null_string] = "string is NULL", + [wrap_json_error_out_of_range] = "array too small", + [wrap_json_error_incomplete] = "incomplete container", + [wrap_json_error_missfit_type] = "missfit of type", + [wrap_json_error_key_not_found] = "key not found" +}; + +int wrap_json_get_error_position(int rc) +{ + if (rc < 0) + rc = -rc; + return (rc >> 4) + 1; +} + +int wrap_json_get_error_code(int rc) +{ + if (rc < 0) + rc = -rc; + return rc & 15; +} + +const char *wrap_json_get_error_string(int rc) +{ + rc = wrap_json_get_error_code(rc); + if (rc >= sizeof pack_errors / sizeof *pack_errors) + rc = 0; + return pack_errors[rc]; +} + + + +static inline const char *skip(const char *d) +{ + while (*d && strchr(ignore_all, *d)) + d++; + return d; +} + +int wrap_json_vpack(struct json_object **result, const char *desc, va_list args) +{ + /* TODO: the case of structs with key being single char should be optimized */ + int nstr, notnull, nullable, rc; + size_t sz, dsz, ssz; + char *s; + char c; + const char *d; + char buffer[256]; + struct { const char *str; size_t sz; } strs[STRCOUNT]; + struct { struct json_object *cont, *key; const char *acc; char type; } stack[STACKCOUNT], *top; + struct json_object *obj; + + ssz = sizeof buffer; + s = buffer; + top = stack; + top->key = NULL; + top->cont = NULL; + top->acc = pack_accept_any; + top->type = 0; + d = desc; + if (!d) + goto null_spec; + d = skip(d); + for(;;) { + c = *d; + if (!c) + goto truncated; + if (!strchr(top->acc, c)) + goto invalid_character; + d = skip(++d); + switch(c) { + case 's': + nullable = 0; + notnull = 0; + nstr = 0; + sz = 0; + for (;;) { + strs[nstr].str = va_arg(args, const char*); + if (strs[nstr].str) + notnull = 1; + if (*d == '?') { + d = skip(++d); + nullable = 1; + } + switch(*d) { + case '%': strs[nstr].sz = va_arg(args, size_t); d = skip(++d); break; + case '#': strs[nstr].sz = (size_t)va_arg(args, int); d = skip(++d); break; + default: strs[nstr].sz = strs[nstr].str ? strlen(strs[nstr].str) : 0; break; + } + sz += strs[nstr++].sz; + if (*d == '?') { + d = skip(++d); + nullable = 1; + } + if (*d != '+') + break; + if (nstr >= STRCOUNT) + goto too_long; + d = skip(++d); + } + if (*d == '*') + nullable = 1; + if (notnull) { + if (sz > ssz) { + ssz += ssz; + if (ssz < sz) + ssz = sz; + s = alloca(sz); + } + dsz = sz; + while (nstr) { + nstr--; + dsz -= strs[nstr].sz; + memcpy(&s[dsz], strs[nstr].str, strs[nstr].sz); + } + obj = json_object_new_string_len(s, (int)sz); + if (!obj) + goto out_of_memory; + } else if (nullable) + obj = NULL; + else + goto null_string; + break; + case 'n': + obj = NULL; + break; + case 'b': + obj = json_object_new_boolean(va_arg(args, int)); + if (!obj) + goto out_of_memory; + break; + case 'i': + obj = json_object_new_int(va_arg(args, int)); + if (!obj) + goto out_of_memory; + break; + case 'I': + obj = json_object_new_int64(va_arg(args, int64_t)); + if (!obj) + goto out_of_memory; + break; + case 'f': + obj = json_object_new_double(va_arg(args, double)); + if (!obj) + goto out_of_memory; + break; + case 'o': + case 'O': + obj = va_arg(args, struct json_object*); + if (*d == '?') + d = skip(++d); + else if (*d != '*' && !obj) + goto null_object; + if (c == 'O') + json_object_get(obj); + break; + case '[': + case '{': + if (++top >= &stack[STACKCOUNT]) + goto too_deep; + top->key = NULL; + if (c == '[') { + top->type = ']'; + top->acc = pack_accept_arr; + top->cont = json_object_new_array(); + } else { + top->type = '}'; + top->acc = pack_accept_key; + top->cont = json_object_new_object(); + } + if (!top->cont) + goto out_of_memory; + continue; + case '}': + case ']': + if (c != top->type || top <= stack) + goto internal_error; + obj = (top--)->cont; + if (*d == '*' && !(c == '}' ? json_object_object_length(obj) : json_object_array_length(obj))) { + json_object_put(obj); + obj = NULL; + } + break; + default: + goto internal_error; + } + switch (top->type) { + case 0: + if (top != stack) + goto internal_error; + if (*d) + goto invalid_character; + *result = obj; + return 0; + case ']': + if (obj || *d != '*') + json_object_array_add(top->cont, obj); + if (*d == '*') + d = skip(++d); + break; + case '}': + if (!obj) + goto null_key; + top->key = obj; + top->acc = pack_accept_any; + top->type = ':'; + break; + case ':': + if (obj || *d != '*') + json_object_object_add(top->cont, json_object_get_string(top->key), obj); + if (*d == '*') + d = skip(++d); + json_object_put(top->key); + top->key = NULL; + top->acc = pack_accept_key; + top->type = '}'; + break; + default: + goto internal_error; + } + } + +null_object: + rc = wrap_json_error_null_object; + goto error; +truncated: + rc = wrap_json_error_truncated; + goto error; +internal_error: + rc = wrap_json_error_internal_error; + goto error; +out_of_memory: + rc = wrap_json_error_out_of_memory; + goto error; +invalid_character: + rc = wrap_json_error_invalid_character; + goto error; +too_long: + rc = wrap_json_error_too_long; + goto error; +too_deep: + rc = wrap_json_error_too_deep; + goto error; +null_spec: + rc = wrap_json_error_null_spec; + goto error; +null_key: + rc = wrap_json_error_null_key; + goto error; +null_string: + rc = wrap_json_error_null_string; + goto error; +error: + do { + json_object_put(top->key); + json_object_put(top->cont); + } while (--top >= stack); + *result = NULL; + rc = rc | (int)((d - desc) << 4); + return -rc; +} + +int wrap_json_pack(struct json_object **result, const char *desc, ...) +{ + int rc; + va_list args; + + va_start(args, desc); + rc = wrap_json_vpack(result, desc, args); + va_end(args); + return rc; +} + +static int vunpack(struct json_object *object, const char *desc, va_list args, int store) +{ + int rc = 0, optionnal, ignore; + char c, xacc[2] = { 0, 0 }; + const char *acc; + const char *d, *fit = NULL; + const char *key = NULL; + const char **ps = NULL; + double *pf = NULL; + int *pi = NULL; + int64_t *pI = NULL; + size_t *pz = NULL; + struct { struct json_object *parent; const char *acc; int index, count; char type; } stack[STACKCOUNT], *top; + struct json_object *obj; + struct json_object **po; + + xacc[0] = 0; + ignore = 0; + top = NULL; + acc = unpack_accept_any; + d = desc; + if (!d) + goto null_spec; + d = skip(d); + obj = object; + for(;;) { + fit = d; + c = *d; + if (!c) + goto truncated; + if (!strchr(acc, c)) + goto invalid_character; + d = skip(++d); + switch(c) { + case 's': + if (xacc[0] == '}') { + /* expects a key */ + key = va_arg(args, const char *); + if (!key) + goto null_key; + if (*d != '?') + optionnal = 0; + else { + optionnal = 1; + d = skip(++d); + } + if (ignore) + ignore++; + else { + if (json_object_object_get_ex(top->parent, key, &obj)) { + /* found */ + top->index++; + } else { + /* not found */ + if (!optionnal) + goto key_not_found; + ignore = 1; + obj = NULL; + } + } + xacc[0] = ':'; + acc = unpack_accept_any; + continue; + } + /* get a string */ + if (store) + ps = va_arg(args, const char **); + if (!ignore) { + if (!json_object_is_type(obj, json_type_string)) + goto missfit; + if (store && ps) + *ps = json_object_get_string(obj); + } + if (*d == '%') { + d = skip(++d); + if (store) { + pz = va_arg(args, size_t *); + if (!ignore && pz) + *pz = (size_t)json_object_get_string_len(obj); + } + } + break; + case 'n': + if (!ignore && !json_object_is_type(obj, json_type_null)) + goto missfit; + break; + case 'b': + if (store) + pi = va_arg(args, int *); + + if (!ignore) { + if (!json_object_is_type(obj, json_type_boolean)) + goto missfit; + if (store && pi) + *pi = json_object_get_boolean(obj); + } + break; + case 'i': + if (store) + pi = va_arg(args, int *); + + if (!ignore) { + if (!json_object_is_type(obj, json_type_int)) + goto missfit; + if (store && pi) + *pi = json_object_get_int(obj); + } + break; + case 'I': + if (store) + pI = va_arg(args, int64_t *); + + if (!ignore) { + if (!json_object_is_type(obj, json_type_int)) + goto missfit; + if (store && pI) + *pI = json_object_get_int64(obj); + } + break; + case 'f': + case 'F': + if (store) + pf = va_arg(args, double *); + + if (!ignore) { + if (!(json_object_is_type(obj, json_type_double) || (c == 'F' && json_object_is_type(obj, json_type_int)))) + goto missfit; + if (store && pf) + *pf = json_object_get_double(obj); + } + break; + case 'o': + case 'O': + if (store) { + po = va_arg(args, struct json_object **); + if (!ignore && po) { + if (c == 'O') + obj = json_object_get(obj); + *po = obj; + } + } + break; + + case '[': + case '{': + if (!top) + top = stack; + else if (++top >= &stack[STACKCOUNT]) + goto too_deep; + + top->acc = acc; + top->type = xacc[0]; + top->index = 0; + top->parent = obj; + if (ignore) + ignore++; + if (c == '[') { + if (!ignore) { + if (!json_object_is_type(obj, json_type_array)) + goto missfit; + top->count = json_object_array_length(obj); + } + xacc[0] = ']'; + acc = unpack_accept_arr; + } else { + if (!ignore) { + if (!json_object_is_type(obj, json_type_object)) + goto missfit; + top->count = json_object_object_length(obj); + } + xacc[0] = '}'; + acc = unpack_accept_key; + continue; + } + break; + case '}': + case ']': + if (!top || c != xacc[0]) + goto internal_error; + acc = top->acc; + xacc[0] = top->type; + top = top == stack ? NULL : top - 1; + if (ignore) + ignore--; + break; + case '!': + if (*d != xacc[0]) + goto invalid_character; + if (!ignore && top->index != top->count) + goto incomplete; + /*@fallthrough@*/ + case '*': + acc = xacc; + continue; + default: + goto internal_error; + } + switch (xacc[0]) { + case 0: + if (top) + goto internal_error; + if (*d) + goto invalid_character; + return 0; + case ']': + if (!ignore) { + key = strchr(unpack_accept_arr, *d); + if (key && key >= unpack_accept_any) { + if (top->index >= top->count) + goto out_of_range; + obj = json_object_array_get_idx(top->parent, top->index++); + } + } + break; + case ':': + acc = unpack_accept_key; + xacc[0] = '}'; + if (ignore) + ignore--; + break; + default: + goto internal_error; + } + } +truncated: + rc = wrap_json_error_truncated; + goto error; +internal_error: + rc = wrap_json_error_internal_error; + goto error; +invalid_character: + rc = wrap_json_error_invalid_character; + goto error; +too_deep: + rc = wrap_json_error_too_deep; + goto error; +null_spec: + rc = wrap_json_error_null_spec; + goto error; +null_key: + rc = wrap_json_error_null_key; + goto error; +out_of_range: + rc = wrap_json_error_out_of_range; + goto error; +incomplete: + rc = wrap_json_error_incomplete; + goto error; +missfit: + rc = wrap_json_error_missfit_type; + goto errorfit; +key_not_found: + rc = wrap_json_error_key_not_found; + goto error; +errorfit: + d = fit; +error: + rc = rc | (int)((d - desc) << 4); + return -rc; +} + +int wrap_json_vcheck(struct json_object *object, const char *desc, va_list args) +{ + return vunpack(object, desc, args, 0); +} + +int wrap_json_check(struct json_object *object, const char *desc, ...) +{ + int rc; + va_list args; + + va_start(args, desc); + rc = vunpack(object, desc, args, 0); + va_end(args); + return rc; +} + +int wrap_json_vmatch(struct json_object *object, const char *desc, va_list args) +{ + return !vunpack(object, desc, args, 0); +} + +int wrap_json_match(struct json_object *object, const char *desc, ...) +{ + int rc; + va_list args; + + va_start(args, desc); + rc = vunpack(object, desc, args, 0); + va_end(args); + return !rc; +} + +int wrap_json_vunpack(struct json_object *object, const char *desc, va_list args) +{ + return vunpack(object, desc, args, 1); +} + +int wrap_json_unpack(struct json_object *object, const char *desc, ...) +{ + int rc; + va_list args; + + va_start(args, desc); + rc = vunpack(object, desc, args, 1); + va_end(args); + return rc; +} + +static void object_for_all(struct json_object *object, void (*callback)(void*,struct json_object*,const char*), void *closure) +{ + struct json_object_iterator it = json_object_iter_begin(object); + struct json_object_iterator end = json_object_iter_end(object); + while (!json_object_iter_equal(&it, &end)) { + callback(closure, json_object_iter_peek_value(&it), json_object_iter_peek_name(&it)); + json_object_iter_next(&it); + } +} + +static void array_for_all(struct json_object *object, void (*callback)(void*,struct json_object*), void *closure) +{ + int n = json_object_array_length(object); + int i = 0; + while(i < n) + callback(closure, json_object_array_get_idx(object, i++)); +} + +void wrap_json_optarray_for_all(struct json_object *object, void (*callback)(void*,struct json_object*), void *closure) +{ + if (json_object_is_type(object, json_type_array)) + array_for_all(object, callback, closure); + else + callback(closure, object); +} + +void wrap_json_array_for_all(struct json_object *object, void (*callback)(void*,struct json_object*), void *closure) +{ + if (json_object_is_type(object, json_type_array)) + array_for_all(object, callback, closure); +} + +void wrap_json_object_for_all(struct json_object *object, void (*callback)(void*,struct json_object*,const char*), void *closure) +{ + if (json_object_is_type(object, json_type_object)) + object_for_all(object, callback, closure); +} + +void wrap_json_optobject_for_all(struct json_object *object, void (*callback)(void*,struct json_object*,const char*), void *closure) +{ + if (json_object_is_type(object, json_type_object)) + object_for_all(object, callback, closure); + else + callback(closure, object, NULL); +} + +void wrap_json_for_all(struct json_object *object, void (*callback)(void*,struct json_object*,const char*), void *closure) +{ + if (!object) + /* do nothing */; + else if (json_object_is_type(object, json_type_object)) + object_for_all(object, callback, closure); + else if (!json_object_is_type(object, json_type_array)) + callback(closure, object, NULL); + else { + int n = json_object_array_length(object); + int i = 0; + while(i < n) + callback(closure, json_object_array_get_idx(object, i++), NULL); + } +} + +#if defined(WRAP_JSON_TEST) +#include <stdio.h> + +void p(const char *desc, ...) +{ + int rc; + va_list args; + struct json_object *result; + + va_start(args, desc); + rc = wrap_json_vpack(&result, desc, args); + va_end(args); + if (!rc) + printf(" SUCCESS %s\n\n", json_object_to_json_string(result)); + else + printf(" ERROR[char %d err %d] %s\n\n", wrap_json_get_error_position(rc), wrap_json_get_error_code(rc), wrap_json_get_error_string(rc)); + json_object_put(result); +} + +const char *xs[10]; +int *xi[10]; +int64_t *xI[10]; +double *xf[10]; +struct json_object *xo[10]; +size_t xz[10]; + +void u(const char *value, const char *desc, ...) +{ + unsigned m, k; + int rc; + va_list args; + struct json_object *obj, *o; + + memset(xs, 0, sizeof xs); + memset(xi, 0, sizeof xi); + memset(xI, 0, sizeof xI); + memset(xf, 0, sizeof xf); + memset(xo, 0, sizeof xo); + memset(xz, 0, sizeof xz); + obj = json_tokener_parse(value); + va_start(args, desc); + rc = wrap_json_vunpack(obj, desc, args); + va_end(args); + if (rc) + printf(" ERROR[char %d err %d] %s\n\n", wrap_json_get_error_position(rc), wrap_json_get_error_code(rc), wrap_json_get_error_string(rc)); + else { + value = NULL; + printf(" SUCCESS"); + va_start(args, desc); + k = m = 0; + while(*desc) { + switch(*desc) { + case '{': m = (m << 1) | 1; k = 1; break; + case '}': m = m >> 1; k = m&1; break; + case '[': m = m << 1; k = 0; break; + case ']': m = m >> 1; k = m&1; break; + case 's': printf(" s:%s", k ? va_arg(args, const char*) : *(va_arg(args, const char**)?:&value)); k ^= m&1; break; + case '%': printf(" %%:%zu", *va_arg(args, size_t*)); k = m&1; break; + case 'n': printf(" n"); k = m&1; break; + case 'b': printf(" b:%d", *va_arg(args, int*)); k = m&1; break; + case 'i': printf(" i:%d", *va_arg(args, int*)); k = m&1; break; + case 'I': printf(" I:%lld", *va_arg(args, int64_t*)); k = m&1; break; + case 'f': printf(" f:%f", *va_arg(args, double*)); k = m&1; break; + case 'F': printf(" F:%f", *va_arg(args, double*)); k = m&1; break; + case 'o': printf(" o:%s", json_object_to_json_string(*va_arg(args, struct json_object**))); k = m&1; break; + case 'O': o = *va_arg(args, struct json_object**); printf(" O:%s", json_object_to_json_string(o)); json_object_put(o); k = m&1; break; + default: break; + } + desc++; + } + va_end(args); + printf("\n\n"); + } + json_object_put(obj); +} + +#define P(...) do{ printf("pack(%s)\n",#__VA_ARGS__); p(__VA_ARGS__); } while(0) +#define U(...) do{ printf("unpack(%s)\n",#__VA_ARGS__); u(__VA_ARGS__); } while(0) + +int main() +{ + char buffer[4] = {'t', 'e', 's', 't'}; + + P("n"); + P("b", 1); + P("b", 0); + P("i", 1); + P("I", (uint64_t)0x123456789abcdef); + P("f", 3.14); + P("s", "test"); + P("s?", "test"); + P("s?", NULL); + P("s#", "test asdf", 4); + P("s%", "test asdf", (size_t)4); + P("s#", buffer, 4); + P("s%", buffer, (size_t)4); + P("s++", "te", "st", "ing"); + P("s#+#+", "test", 1, "test", 2, "test"); + P("s%+%+", "test", (size_t)1, "test", (size_t)2, "test"); + P("{}", 1.0); + P("[]", 1.0); + P("o", json_object_new_int(1)); + P("o?", json_object_new_int(1)); + P("o?", NULL); + P("O", json_object_new_int(1)); + P("O?", json_object_new_int(1)); + P("O?", NULL); + P("{s:[]}", "foo"); + P("{s+#+: []}", "foo", "barbar", 3, "baz"); + P("{s:s,s:o,s:O}", "a", NULL, "b", NULL, "c", NULL); + P("{s:**}", "a", NULL); + P("{s:s*,s:o*,s:O*}", "a", NULL, "b", NULL, "c", NULL); + P("[i,i,i]", 0, 1, 2); + P("[s,o,O]", NULL, NULL, NULL); + P("[**]", NULL); + P("[s*,o*,O*]", NULL, NULL, NULL); + P(" s ", "test"); + P("[ ]"); + P("[ i , i, i ] ", 1, 2, 3); + P("{\n\n1"); + P("[}"); + P("{]"); + P("["); + P("{"); + P("[i]a", 42); + P("ia", 42); + P("s", NULL); + P("+", NULL); + P(NULL); + P("{s:i}", NULL, 1); + P("{ {}: s }", "foo"); + P("{ s: {}, s:[ii{} }", "foo", "bar", 12, 13); + P("[[[[[ [[[[[ [[[[ }]]]] ]]]] ]]]]]"); + + U("true", "b", &xi[0]); + U("false", "b", &xi[0]); + U("null", "n"); + U("42", "i", &xi[0]); + U("123456789", "I", &xI[0]); + U("3.14", "f", &xf[0]); + U("12345", "F", &xf[0]); + U("3.14", "F", &xf[0]); + U("\"foo\"", "s", &xs[0]); + U("\"foo\"", "s%", &xs[0], &xz[0]); + U("{}", "{}"); + U("[]", "[]"); + U("{}", "o", &xo[0]); + U("{}", "O", &xo[0]); + U("{\"foo\":42}", "{si}", "foo", &xi[0]); + U("[1,2,3]", "[i,i,i]", &xi[0], &xi[1], &xi[2]); + U("{\"a\":1,\"b\":2,\"c\":3}", "{s:i, s:i, s:i}", "a", &xi[0], "b", &xi[1], "c", &xi[2]); + U("42", "z"); + U("null", "[i]"); + U("[]", "[}"); + U("{}", "{]"); + U("[]", "["); + U("{}", "{"); + U("[42]", "[i]a", &xi[0]); + U("42", "ia", &xi[0]); + U("[]", NULL); + U("\"foo\"", "s", NULL); + U("42", "s", NULL); + U("42", "n"); + U("42", "b", NULL); + U("42", "f", NULL); + U("42", "[i]", NULL); + U("42", "{si}", "foo", NULL); + U("\"foo\"", "n"); + U("\"foo\"", "b", NULL); + U("\"foo\"", "i", NULL); + U("\"foo\"", "I", NULL); + U("\"foo\"", "f", NULL); + U("\"foo\"", "F", NULL); + U("true", "s", NULL); + U("true", "n"); + U("true", "i", NULL); + U("true", "I", NULL); + U("true", "f", NULL); + U("true", "F", NULL); + U("[42]", "[ii]", &xi[0], &xi[1]); + U("{\"foo\":42}", "{si}", NULL, &xi[0]); + U("{\"foo\":42}", "{si}", "baz", &xi[0]); + U("[1,2,3]", "[iii!]", &xi[0], &xi[1], &xi[2]); + U("[1,2,3]", "[ii!]", &xi[0], &xi[1]); + U("[1,2,3]", "[ii]", &xi[0], &xi[1]); + U("[1,2,3]", "[ii*]", &xi[0], &xi[1]); + U("{\"foo\":42,\"baz\":45}", "{sisi}", "baz", &xi[0], "foo", &xi[1]); + U("{\"foo\":42,\"baz\":45}", "{sisi*}", "baz", &xi[0], "foo", &xi[1]); + U("{\"foo\":42,\"baz\":45}", "{sisi!}", "baz", &xi[0], "foo", &xi[1]); + U("{\"foo\":42,\"baz\":45}", "{si}", "baz", &xi[0], "foo", &xi[1]); + U("{\"foo\":42,\"baz\":45}", "{si*}", "baz", &xi[0], "foo", &xi[1]); + U("{\"foo\":42,\"baz\":45}", "{si!}", "baz", &xi[0], "foo", &xi[1]); + U("[1,{\"foo\":2,\"bar\":null},[3,4]]", "[i{sisn}[ii]]", &xi[0], "foo", &xi[1], "bar", &xi[2], &xi[3]); + U("[1,2,3]", "[ii!i]", &xi[0], &xi[1], &xi[2]); + U("[1,2,3]", "[ii*i]", &xi[0], &xi[1], &xi[2]); + U("{\"foo\":1,\"bar\":2}", "{si!si}", "foo", &xi[1], "bar", &xi[2]); + U("{\"foo\":1,\"bar\":2}", "{si*si}", "foo", &xi[1], "bar", &xi[2]); + U("{\"foo\":{\"baz\":null,\"bar\":null}}", "{s{sn!}}", "foo", "bar"); + U("[[1,2,3]]", "[[ii!]]", &xi[0], &xi[1]); + U("{}", "{s?i}", "foo", &xi[0]); + U("{\"foo\":1}", "{s?i}", "foo", &xi[0]); + U("{}", "{s?[ii]s?{s{si!}}}", "foo", &xi[0], &xi[1], "bar", "baz", "quux", &xi[2]); + U("{\"foo\":[1,2]}", "{s?[ii]s?{s{si!}}}", "foo", &xi[0], &xi[1], "bar", "baz", "quux", &xi[2]); + U("{\"bar\":{\"baz\":{\"quux\":15}}}", "{s?[ii]s?{s{si!}}}", "foo", &xi[0], &xi[1], "bar", "baz", "quux", &xi[2]); + U("{\"foo\":{\"bar\":4}}", "{s?{s?i}}", "foo", "bar", &xi[0]); + U("{\"foo\":{}}", "{s?{s?i}}", "foo", "bar", &xi[0]); + U("{}", "{s?{s?i}}", "foo", "bar", &xi[0]); + U("{\"foo\":42,\"baz\":45}", "{s?isi!}", "baz", &xi[0], "foo", &xi[1]); + U("{\"foo\":42}", "{s?isi!}", "baz", &xi[0], "foo", &xi[1]); + return 0; +} + +#endif + +#if 0 + + + /* Unpack the same item twice */ + j = json_pack("{s:s, s:i, s:b}", "foo", "bar", "baz", 42, "quux", 1); + if(!json_unpack_ex(j, &error, 0, "{s:s,s:s!}", "foo", &s, "foo", &s)) + fail("json_unpack object with strict validation failed"); + { + const char *possible_errors[] = { + "2 object item(s) left unpacked: baz, quux", + "2 object item(s) left unpacked: quux, baz" + }; + check_errors(possible_errors, 2, "<validation>", 1, 10, 10); + } + json_decref(j); + +#endif diff --git a/afb-utilities/wrap-json.h b/afb-utilities/wrap-json.h new file mode 100644 index 0000000..cb2d0bf --- /dev/null +++ b/afb-utilities/wrap-json.h @@ -0,0 +1,46 @@ +/* + Copyright (C) 2016, 2017 "IoT.bzh" + + author: José Bollo <jose.bollo@iot.bzh> + + Licensed under the Apache License, Version 2.0 (the "License"); + you may not use this file except in compliance with the License. + You may obtain a copy of the License at + + http://www.apache.org/licenses/LICENSE-2.0 + + Unless required by applicable law or agreed to in writing, software + distributed under the License is distributed on an "AS IS" BASIS, + WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. + See the License for the specific language governing permissions and + limitations under the License. +*/ + +#pragma once + +#include <stdarg.h> +#include <json-c/json.h> + +extern int wrap_json_get_error_position(int rc); +extern int wrap_json_get_error_code(int rc); +extern const char *wrap_json_get_error_string(int rc); + +extern int wrap_json_vpack(struct json_object **result, const char *desc, va_list args); +extern int wrap_json_pack(struct json_object **result, const char *desc, ...); + +extern int wrap_json_vunpack(struct json_object *object, const char *desc, va_list args); +extern int wrap_json_unpack(struct json_object *object, const char *desc, ...); +extern int wrap_json_vcheck(struct json_object *object, const char *desc, va_list args); +extern int wrap_json_check(struct json_object *object, const char *desc, ...); +extern int wrap_json_vmatch(struct json_object *object, const char *desc, va_list args); +extern int wrap_json_match(struct json_object *object, const char *desc, ...); + +extern void wrap_json_optarray_for_all(struct json_object *object, void (*callback)(void*,struct json_object*), void *closure); +extern void wrap_json_array_for_all(struct json_object *object, void (*callback)(void*,struct json_object*), void *closure); + +extern void wrap_json_optarray_for_all(struct json_object *object, void (*callback)(void*,struct json_object*), void *closure); +extern void wrap_json_array_for_all(struct json_object *object, void (*callback)(void*,struct json_object*), void *closure); +extern void wrap_json_object_for_all(struct json_object *object, void (*callback)(void*,struct json_object*,const char*), void *closure); +extern void wrap_json_optobject_for_all(struct json_object *object, void (*callback)(void*,struct json_object*,const char*), void *closure); +extern void wrap_json_for_all(struct json_object *object, void (*callback)(void*,struct json_object*,const char*), void *closure); + diff --git a/afb-utilities/wrap-json.md b/afb-utilities/wrap-json.md new file mode 100644 index 0000000..92940f1 --- /dev/null +++ b/afb-utilities/wrap-json.md @@ -0,0 +1,305 @@ +WRAP-JSON facility +================== + +The facility wrap-json is based on the pack/unpack API on the +libray jansson. The two chapters below are copied from the +documentation of jansson library copyrighted by Petri Lehtinen +(see at end). + +Building Values +--------------- + +This section describes functions that help to create, or *pack*, complex +JSON values, especially nested objects and arrays. Value building is +based on a *format string* that is used to tell the functions about the +expected arguments. + +For example, the format string `"i"` specifies a single integer value, +while the format string `"[ssb]"` or the equivalent `"[s, s, b]"` +specifies an array value with two strings and a boolean as its items: + + /* Create the JSON integer 42 */ + wrap_json_pack(&result, "i", 42); + + /* Create the JSON array ["foo", "bar", true] */ + wrap_json_pack(&result, "[ssb]", "foo", "bar", 1); + +Here's the full list of format specifiers. The type in parentheses +denotes the resulting JSON type, and the type in brackets (if any) +denotes the C type that is expected as the corresponding argument or +arguments. + +`s` (string) \[const char \*\] + +: Convert a null terminated UTF-8 string to a JSON string. + +`s?` (string) \[const char \*\] + +: Like `s`, but if the argument is *NULL*, output a JSON null value. + +`s*` (string) \[const char \*\] + +: Like `s`, but if the argument is *NULL*, do not output any value. + This format can only be used inside an object or an array. If used + inside an object, the corresponding key is additionally suppressed + when the value is omitted. See below for an example. + +`s#` (string) \[const char \*, int\] + +: Convert a UTF-8 buffer of a given length to a JSON string. + +`s%` (string) \[const char \*, size\_t\] + +: Like `s#` but the length argument is of type size\_t. + +`+` \[const char \*\] + +: Like `s`, but concatenate to the previous string. Only valid after + `s`, `s#`, `+` or `+#`. + +`+#` \[const char \*, int\] + +: Like `s#`, but concatenate to the previous string. Only valid after + `s`, `s#`, `+` or `+#`. + +`+%` (string) \[const char \*, size\_t\] + +: Like `+#` but the length argument is of type size\_t. + +`n` (null) + +: Output a JSON null value. No argument is consumed. + +`b` (boolean) \[int\] + +: Convert a C int to JSON boolean value. Zero is converted to `false` + and non-zero to `true`. + +`i` (integer) \[int\] + +: Convert a C int to JSON integer. + +`I` (integer) \[json\_int\_t\] + +: Convert a C json\_int\_t to JSON integer. + +`f` (real) \[double\] + +: Convert a C double to JSON real. + +`o` (any value) \[json\_t \*\] + +: Output any given JSON value as-is. If the value is added to an array + or object, the reference to the value passed to `o` is stolen by the + container. + +`O` (any value) \[json\_t \*\] + +: Like `o`, but the argument's reference count is incremented. This is + useful if you pack into an array or object and want to keep the + reference for the JSON value consumed by `O` to yourself. + +`o?`, `O?` (any value) \[json\_t \*\] + +: Like `o` and `O`, respectively, but if the argument is *NULL*, + output a JSON null value. + +`o*`, `O*` (any value) \[json\_t \*\] + +: Like `o` and `O`, respectively, but if the argument is *NULL*, do + not output any value. This format can only be used inside an object + or an array. If used inside an object, the corresponding key is + additionally suppressed. See below for an example. + +`[fmt]` (array) + +: Build an array with contents from the inner format string. `fmt` may + contain objects and arrays, i.e. recursive value building is + supported. + +`{fmt}` (object) + +: Build an object with contents from the inner format string `fmt`. + The first, third, etc. format specifier represent a key, and must be + a string (see `s`, `s#`, `+` and `+#` above), as object keys are + always strings. The second, fourth, etc. format specifier represent + a value. Any value may be an object or array, i.e. recursive value + building is supported. + +Whitespace, `:` and `,` are ignored. + +More examples: + + /* Build an empty JSON object */ + wrap_json_pack(&result, "{}"); + + /* Build the JSON object {"foo": 42, "bar": 7} */ + wrap_json_pack(&result, "{sisi}", "foo", 42, "bar", 7); + + /* Like above, ':', ',' and whitespace are ignored */ + wrap_json_pack(&result, "{s:i, s:i}", "foo", 42, "bar", 7); + + /* Build the JSON array [[1, 2], {"cool": true}] */ + wrap_json_pack(&result, "[[i,i],{s:b}]", 1, 2, "cool", 1); + + /* Build a string from a non-null terminated buffer */ + char buffer[4] = {'t', 'e', 's', 't'}; + wrap_json_pack(&result, "s#", buffer, 4); + + /* Concatenate strings together to build the JSON string "foobarbaz" */ + wrap_json_pack(&result, "s++", "foo", "bar", "baz"); + + /* Create an empty object or array when optional members are missing */ + wrap_json_pack(&result, "{s:s*,s:o*,s:O*}", "foo", NULL, "bar", NULL, "baz", NULL); + wrap_json_pack(&result, "[s*,o*,O*]", NULL, NULL, NULL); + +Parsing and Validating Values +----------------------------- + +This section describes functions that help to validate complex values +and extract, or *unpack*, data from them. Like building values +<apiref-pack>, this is also based on format strings. + +While a JSON value is unpacked, the type specified in the format string +is checked to match that of the JSON value. This is the validation part +of the process. In addition to this, the unpacking functions can also +check that all items of arrays and objects are unpacked. This check be +enabled with the format specifier `!` or by using the flag +`JSON_STRICT`. See below for details. + +Here's the full list of format specifiers. The type in parentheses +denotes the JSON type, and the type in brackets (if any) denotes the C +type whose address should be passed. + +`s` (string) \[const char \*\] + +: Convert a JSON string to a pointer to a null terminated UTF-8 + string. The resulting string is extracted by using + json\_string\_value() internally, so it exists as long as there are + still references to the corresponding JSON string. + +`s%` (string) \[const char \*, size\_t \*\] + +: Convert a JSON string to a pointer to a null terminated UTF-8 string + and its length. + +`n` (null) + +: Expect a JSON null value. Nothing is extracted. + +`b` (boolean) \[int\] + +: Convert a JSON boolean value to a C int, so that `true` is converted + to 1 and `false` to 0. + +`i` (integer) \[int\] + +: Convert a JSON integer to C int. + +`I` (integer) \[json\_int\_t\] + +: Convert a JSON integer to C json\_int\_t. + +`f` (real) \[double\] + +: Convert a JSON real to C double. + +`F` (integer or real) \[double\] + +: Convert a JSON number (integer or real) to C double. + +`o` (any value) \[json\_t \*\] + +: Store a JSON value with no conversion to a json\_t pointer. + +`O` (any value) \[json\_t \*\] + +: Like `O`, but the JSON value's reference count is incremented. + +`[fmt]` (array) + +: Convert each item in the JSON array according to the inner format + string. `fmt` may contain objects and arrays, i.e. recursive value + extraction is supported. + +`{fmt}` (object) + +: Convert each item in the JSON object according to the inner format + string `fmt`. The first, third, etc. format specifier represent a + key, and must be `s`. The corresponding argument to unpack functions + is read as the object key. The second fourth, etc. format specifier + represent a value and is written to the address given as the + corresponding argument. **Note** that every other argument is read + from and every other is written to. + + `fmt` may contain objects and arrays as values, i.e. recursive value + extraction is supported. + +`!` + +: This special format specifier is used to enable the check that all + object and array items are accessed, on a per-value basis. It must + appear inside an array or object as the last format specifier before + the closing bracket or brace. + +`*` + +: This special format specifier is the opposite of `!`. This is the default. + It must appear inside an array or object as the last format specifier + before the closing bracket or brace. + +Whitespace, `:` and `,` are ignored. + +Examples: + + /* root is the JSON integer 42 */ + int myint; + wrap_json_unpack(root, "i", &myint); + assert(myint == 42); + + /* root is the JSON object {"foo": "bar", "quux": true} */ + const char *str; + int boolean; + wrap_json_unpack(root, "{s:s, s:b}", "foo", &str, "quux", &boolean); + assert(strcmp(str, "bar") == 0 && boolean == 1); + + /* root is the JSON array [[1, 2], {"baz": null} */ + wrap_json_check(root, "[[i,i], {s:n}]", "baz"); + /* returns 0 for validation success, nothing is extracted */ + + /* root is the JSON array [1, 2, 3, 4, 5] */ + int myint1, myint2; + wrap_json_unpack(root, "[ii!]", &myint1, &myint2); + /* returns -1 for failed validation */ + + /* root is an empty JSON object */ + int myint = 0, myint2 = 0, myint3 = 0; + wrap_json_unpack(root, "{s?i, s?[ii]}", + "foo", &myint1, + "bar", &myint2, &myint3); + /* myint1, myint2 or myint3 is no touched as "foo" and "bar" don't exist */ + + +Copyright +--------- + +Copyright (c) 2009-2016 Petri Lehtinen <petri@digip.org> + +Permission is hereby granted, free of charge, to any person obtaining a copy +of this software and associated documentation files (the "Software"), to deal +in the Software without restriction, including without limitation the rights +to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +copies of the Software, and to permit persons to whom the Software is +furnished to do so, subject to the following conditions: + +The above copyright notice and this permission notice shall be included in +all copies or substantial portions of the Software. + +THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +THE SOFTWARE. + |