1 /* Copyright 2003-2019, University Corporation for Atmospheric
2  * Research. See the COPYRIGHT file for copying and redistribution
3  * conditions. */
4 /**
5  * @file @internal This file is part of netcdf-4, a netCDF-like
6  * interface for HDF5, or a HDF5 backend for netCDF, depending on your
7  * point of view.
8  *
9  * This file includes the HDF5 code to deal with dimensions.
10  *
11  * @author Ed Hartnett
12  */
13 
14 #include "config.h"
15 #include "hdf5internal.h"
16 
17 /**
18  * @internal Dimensions are defined in attributes attached to the
19  * appropriate group in the data file.
20  *
21  * @param ncid File and group ID.
22  * @param name Name of the new dimension.
23  * @param len Length of the new dimension.
24  * @param idp Pointer that gets the ID of the new dimension. Ignored
25  * if NULL.
26  *
27  * @return ::NC_NOERR No error.
28  * @return ::NC_EBADID Bad ncid.
29  * @return ::NC_EMAXNAME Name is too long.
30  * @return ::NC_EBADNAME Name breaks netCDF name rules.
31  * @return ::NC_EINVAL Invalid input.
32  * @return ::NC_EPERM Read-only file.
33  * @return ::NC_EUNLIMIT Only one unlimited dim for classic model.
34  * @return ::NC_ENOTINDEFINE Not in define mode.
35  * @return ::NC_EDIMSIZE Dim length too large.
36  * @return ::NC_ENAMEINUSE Name already in use in group.
37  * @return ::NC_ENOMEM Out of memory.
38  * @author Ed Hartnett
39  */
40 int
NC4_def_dim(int ncid,const char * name,size_t len,int * idp)41 NC4_def_dim(int ncid, const char *name, size_t len, int *idp)
42 {
43     NC *nc;
44     NC_GRP_INFO_T *grp;
45     NC_FILE_INFO_T *h5;
46     NC_DIM_INFO_T *dim;
47     char norm_name[NC_MAX_NAME + 1];
48     int retval = NC_NOERR;
49     int i;
50 
51     LOG((2, "%s: ncid 0x%x name %s len %d", __func__, ncid, name,
52          (int)len));
53 
54     /* Find our global metadata structure. */
55     if ((retval = nc4_find_nc_grp_h5(ncid, &nc, &grp, &h5)))
56         return retval;
57     assert(h5 && nc && grp);
58 
59     /* If the file is read-only, return an error. */
60     if (h5->no_write)
61         return NC_EPERM;
62 
63     /* Check some stuff if strict nc3 rules are in effect. */
64     if (h5->cmode & NC_CLASSIC_MODEL)
65     {
66         /* Only one limited dimenson for strict nc3. */
67         if (len == NC_UNLIMITED) {
68             for(i=0;i<ncindexsize(grp->dim);i++) {
69                 dim = (NC_DIM_INFO_T*)ncindexith(grp->dim,i);
70                 if(dim == NULL) continue;
71                 if (dim->unlimited)
72                     return NC_EUNLIMIT;
73             }
74         }
75         /* Must be in define mode for stict nc3. */
76         if (!(h5->flags & NC_INDEF))
77             return NC_ENOTINDEFINE;
78     }
79 
80     /* Make sure this is a valid netcdf name. */
81     if ((retval = nc4_check_name(name, norm_name)))
82         return retval;
83 
84     /* For classic model: dim length has to fit in a 32-bit unsigned
85      * int, as permitted for 64-bit offset format. */
86     if (h5->cmode & NC_CLASSIC_MODEL)
87         if(len > X_UINT_MAX) /* Backward compat */
88             return NC_EDIMSIZE;
89 
90     /* Make sure the name is not already in use. */
91     dim = (NC_DIM_INFO_T*)ncindexlookup(grp->dim,norm_name);
92     if(dim != NULL)
93         return NC_ENAMEINUSE;
94 
95     /* If it's not in define mode, enter define mode. Do this only
96      * after checking all input data, so we only enter define mode if
97      * input is good. */
98     if (!(h5->flags & NC_INDEF))
99         if ((retval = NC4_redef(ncid)))
100             return retval;
101 
102     /* Add a dimension to the list. The ID must come from the file
103      * information, since dimids are visible in more than one group. */
104     if ((retval = nc4_dim_list_add(grp, norm_name, len, -1, &dim)))
105         return retval;
106 
107     /* Create struct for HDF5-specific dim info. */
108     if (!(dim->format_dim_info = calloc(1, sizeof(NC_HDF5_DIM_INFO_T))))
109         return NC_ENOMEM;
110 
111     /* Pass back the dimid. */
112     if (idp)
113         *idp = dim->hdr.id;
114 
115     return retval;
116 }
117 
118 /**
119  * @internal Find out name and len of a dim. For an unlimited
120  * dimension, the length is the largest length so far written. If the
121  * name of lenp pointers are NULL, they will be ignored.
122  *
123  * @param ncid File and group ID.
124  * @param dimid Dimension ID.
125  * @param name Pointer that gets name of the dimension.
126  * @param lenp Pointer that gets length of dimension.
127  *
128  * @return ::NC_NOERR No error.
129  * @return ::NC_EBADID Bad ncid.
130  * @return ::NC_EDIMSIZE Dimension length too large.
131  * @return ::NC_EBADDIM Dimension not found.
132  * @author Ed Hartnett
133  */
134 int
NC4_inq_dim(int ncid,int dimid,char * name,size_t * lenp)135 NC4_inq_dim(int ncid, int dimid, char *name, size_t *lenp)
136 {
137     NC *nc;
138     NC_FILE_INFO_T *h5;
139     NC_GRP_INFO_T *grp, *dim_grp;
140     NC_DIM_INFO_T *dim;
141     int ret = NC_NOERR;
142 
143     LOG((2, "%s: ncid 0x%x dimid %d", __func__, ncid, dimid));
144 
145     /* Find our global metadata structure. */
146     if ((ret = nc4_find_nc_grp_h5(ncid, &nc, &grp, &h5)))
147         return ret;
148     assert(h5 && nc && grp);
149 
150     /* Find the dimension and its home group. */
151     if ((ret = nc4_find_dim(grp, dimid, &dim, &dim_grp)))
152         return ret;
153     assert(dim);
154 
155     /* Return the dimension name, if the caller wants it. */
156     if (name && dim->hdr.name)
157         strcpy(name, dim->hdr.name);
158 
159     /* Return the dimension length, if the caller wants it. */
160     if (lenp)
161     {
162         if (dim->unlimited)
163         {
164             /* Since this is an unlimited dimension, go to the file
165                and see how many records there are. Take the max number
166                of records from all the vars that share this
167                dimension. */
168             *lenp = 0;
169             if ((ret = nc4_find_dim_len(dim_grp, dimid, &lenp)))
170                 return ret;
171         }
172         else
173         {
174             if (dim->too_long)
175             {
176                 ret = NC_EDIMSIZE;
177                 *lenp = NC_MAX_UINT;
178             }
179             else
180                 *lenp = dim->len;
181         }
182     }
183 
184     return ret;
185 }
186 
187 /**
188  * @internal Rename a dimension, for those who like to prevaricate.
189  *
190  * @note If we're not in define mode, new name must be of equal or
191  * less size, if strict nc3 rules are in effect for this file. But we
192  * don't check this because reproducing the exact classic behavior
193  * would be too difficult. See github issue #1340.
194  *
195  * @param ncid File and group ID.
196  * @param dimid Dimension ID.
197  * @param name New dimension name.
198  *
199  * @return ::NC_NOERR No error.
200  * @return ::NC_EBADID Bad ncid.
201  * @return ::NC_EHDFERR HDF5 returned error.
202  * @return ::NC_ENOMEM Out of memory.
203  * @return ::NC_EINVAL Name must be provided.
204  * @return ::NC_ENAMEINUSE Name is already in use in group.
205  * @return ::NC_EMAXNAME Name is too long.
206  * @return ::NC_EBADDIM Dimension not found.
207  * @return ::NC_EBADNAME Name breaks netCDF name rules.
208  * @return ::NC_EDIMMETA Unable to delete HDF5 dataset.
209  * @author Ed Hartnett
210  */
211 int
NC4_rename_dim(int ncid,int dimid,const char * name)212 NC4_rename_dim(int ncid, int dimid, const char *name)
213 {
214     NC_GRP_INFO_T *grp;
215     NC_DIM_INFO_T *dim;
216     NC_HDF5_DIM_INFO_T *hdf5_dim;
217     NC_FILE_INFO_T *h5;
218     char norm_name[NC_MAX_NAME + 1];
219     int retval;
220 
221     /* Note: name is new name */
222     if (!name)
223         return NC_EINVAL;
224 
225     LOG((2, "%s: ncid 0x%x dimid %d name %s", __func__, ncid,
226          dimid, name));
227 
228     /* Find info for this file and group, and set pointer to each. */
229     if ((retval = nc4_find_grp_h5(ncid, &grp, &h5)))
230         return retval;
231     assert(h5 && grp);
232 
233     /* Trying to write to a read-only file? No way, Jose! */
234     if (h5->no_write)
235         return NC_EPERM;
236 
237     /* Make sure this is a valid netcdf name. */
238     if ((retval = nc4_check_name(name, norm_name)))
239         return retval;
240 
241     /* Get the original dim. */
242     if ((retval = nc4_find_dim(grp, dimid, &dim, NULL)))
243         return retval;
244     assert(dim && dim->format_dim_info);
245     hdf5_dim = (NC_HDF5_DIM_INFO_T *)dim->format_dim_info;
246 
247     /* Check if new name is in use. */
248     if (ncindexlookup(grp->dim, norm_name))
249         return NC_ENAMEINUSE;
250 
251     /* Check for renaming dimension w/o variable. */
252     if (hdf5_dim->hdf_dimscaleid)
253     {
254         assert(!dim->coord_var);
255         LOG((3, "dim %s is a dim without variable", dim->hdr.name));
256 
257         /* Delete the dimscale-only dataset. */
258         if ((retval = delete_dimscale_dataset(grp, dimid, dim)))
259             return retval;
260     }
261 
262     /* Give the dimension its new name in metadata. UTF8 normalization
263      * has been done. */
264     assert(dim->hdr.name);
265     free(dim->hdr.name);
266     if (!(dim->hdr.name = strdup(norm_name)))
267         return NC_ENOMEM;
268     LOG((3, "dim is now named %s", dim->hdr.name));
269 
270     /* Fix hash key and rebuild index. */
271     dim->hdr.hashkey = NC_hashmapkey(dim->hdr.name,strlen(dim->hdr.name));
272     if (!ncindexrebuild(grp->dim))
273         return NC_EINTERNAL;
274 
275     /* Check if dimension was a coordinate variable, but names are
276      * different now. */
277     if (dim->coord_var && strcmp(dim->hdr.name, dim->coord_var->hdr.name))
278     {
279         /* Break up the coordinate variable. */
280         if ((retval = nc4_break_coord_var(grp, dim->coord_var, dim)))
281             return retval;
282     }
283 
284     /* Check if dimension should become a coordinate variable. */
285     if (!dim->coord_var)
286     {
287         NC_VAR_INFO_T *var;
288 
289         /* Attempt to find a variable with the same name as the
290          * dimension in the current group. */
291         if ((retval = nc4_find_var(grp, dim->hdr.name, &var)))
292             return retval;
293 
294         /* Check if we found a variable and the variable has the
295          * dimension in index 0. */
296         if (var && var->dim[0] == dim)
297         {
298             /* Sanity check */
299             assert(var->dimids[0] == dim->hdr.id);
300 
301             /* Reform the coordinate variable. */
302             if ((retval = nc4_reform_coord_var(grp, var, dim)))
303                 return retval;
304         }
305     }
306 
307     return NC_NOERR;
308 }
309